I think that these chambers really need some change. They need to all be equally viable, in it's own way. They also need to be more different, and focus on more things than just attacking (right now each chamber is just used to attack with). So, I'm going to drastically change them all, and add a new chamber, the Stamina Chamber (StC). The chambers will be listed at the top, and their upgrades will be listed at the bottom.
DC: The defensive chamber is chained to hives, just like now. 1500 health. A defensive chamber costs 15 resources. They can only be placed within healing range of a hive, somewhere where a hive can be built, or within the range of an MC (in which case a DC's range is no longer just the healing range of the hive, but is 500 units). A defensive chamber will heal all chambers and aliens within healing range of the hive at a rate of 30 health/second. Also, when the aliens have 80% of their team dead, for the next 30 seconds, each DC within range of that specific hive will raise spawn speed by 6% (allowing a 48% faster spawn for 30 seconds). When a hive is under attack for a total of 1500 damage in under 10 seconds (which means that the hive would be in danger, and most likely under attack be more than one marine), each defensive chamber within range will pull one alien back to the hive (if there are not enough aliens alive, it will respawn AND pull dead aliens to that hive). If the alien is selected to be pulled back, the alien will be given the choice if it wants to be pulled back, and can select Yes by pressing "1", and select No by pressing "2". When a hive is under excrutiating attack (the same as when an alien is being pulled back), the DC will release umbra toward the hive, much like lerk umbra, only blocking just 1/4 bullets. However, this umbra can stack with other DC umbra, and lerk's umbra. When the DC is placed within range of an MC and not a hive, the umbra is given to aliens under attack and nearby structures under attack. The healing is also given, but all other abilities are failed. The defensive chamber is targeted mostly at protecting hives.
MC: Once an MC is built, an alien can "+use" the hive to be transported randomly to one of the other 2 hives, unless a hive is under attack, in which case the alien will go to that hive with a 100% efficiency. An MC is chained to hives. 1200 health. It costs 15 resources to build. An MC can be built anywhere around the map. The range of MCs is 600 units - which all of these effects take place in. OCs and DCs can be built within range of an MC. Also, MCs will raise an alien's speed within range by 8%. This does stack. This allows aliens nearby to become extremely fast with enough chambers, and also alows "MC chains", much like SC chains, to cover the entire map. Aliens will also have a 25% increase to energy every other second when within range. Building and gestating both are decreased in time by 5% when within MC range. Any chamber effects (other than Hive and RT) will be sped up by 5% when within range. These all stack with other nearby MCs. The movement chamber is targeted at fast map-expansion (and is hence viable for any hive number).
SC: Sensory chambers are chained to hives. It costs 15 resources to build. 1100 health. A sensory chamber's range is 800 units. No other sensory chambers can be built within this range. Any marine within the range shows up on hive-sight as a blue circle. This circle will be a lighter color when the marine has a higher health and armor, and will be darker when the marine has a lower health and armor. The sensory chamber cloaks all chambers and aliens to 100% when they have been within range for 3.5 seconds. If a marine or marine structure attacks a cloaked sensory chamber, (which will no longer show up on the marine mini-map at any time) the marine will become parasited, and will take 10 damage. This may happen up to 1 time every 10 seconds. The same occurs when a marine touches a hive that is cloaked. The SC will block observatory...observing. It will not block scanning, however. When placed within range of a marine structure, you can tell what it is researching (if anything). The sensory chamber is targeted at expanding the alien's senses, and lowering any marine surprise action.
Offensive Chamber (OC): 1250 health. 12 resources. Buildable once one hive is complete (the first hive). The OC will increase alien's offensive power. The range is 700 units. It provides no upgrades. Any alien or structure within range will gain 15% more damage on each one of its attacks. Also, a marine within range and within LoS will will be shot at with a spike that deals 20 damage. This spike has a RoF of ~ 1/second. An Offense chamber can only be built within the hive's range, 400 units of an RT, or an MC's range. Focuses on protecting hives and destroying bases.
Stamina Chamber (StC): Buildable within range of any active chamber or hive at any time of the game. Costs 5 resources. 600 health. The Stamina Chamber will raise any chamber within 450 unit's health by 6.25%. Also, any alien within range can "+use" the chamber for an extra 20% health and armor, which will tick down for the next 10 seconds back to what it should be. It will heal any nearby aliens by 8 damage every other second. Useful for base takedown. Provides no upgrades. Focuses on allowing aliens to continually attack marines.
So, now the chambers are more viable, and all have certain disadvantages to them, as well as advantages.
Upgrades: Each chamber has 4 upgrades instead of 3 to choose from.
DC:
Regeneration: When an alien has lower than 40% of it's health, it will start regenerating health. Each level adds a 6% health/second regeneration when lower than 40% health, making regeneration more of a life-saving ability like redemption than a constant attack attack attack ability.
Redemption: When an alien has lower than 40% of it's health, there is a 50% chance/second/level that the alien will redempt back to the hive for healing.
Carapace: The alien will increase it's armor by 33.3% of it's normal armor per level (making it slightly less viable for skulk, equally viable for gorge and lerk, and more viable for fade and onos).
Healing: An alien will give out an AoE healing. This will heal 3 health + 4% health/second to any aliens within 200, 40 and 600 units from level 1-3 (think of the effects of a 6 person alien team all getting this upgrade and attacking a marine base. That's 18 + 24% health/second healing to each one of them).
MC:
Silence: An alien will be silenced to 50%, 15% and 0% noise from level 1-3.
Celerity: An alien will gain 13% more speed with each level.
Frenzy: An alien's RoF of each of it's attacks will be increased by 10% with each level.
Adrenaline: An alien will gain energy 33%, 66% and 100% faster with each level from 1-3.
SC:
Scent of fear: Each level will show marines on hive-sight from 1-3 within 800, 1600 and 2400. A marine will show up as green, blue, violet, red or black, depending on it's percent of health and armor it has left:
Green: 85-100%.
Blue: 65-84%.
Violet: 50-64%.
Red: 25-49%.
Black: 1-24%.
Amplify: All ambient sounds will be made less loud by 25, 50 and 75% from level 1-3. This allows aliens to hear when a marine is coming, building, etc. Also, all marine sounds can be heard from 100, 200 and 300 units further away from levels 1-3.
Cloaking: At level 1, an alien will cloak within 3 seconds of not moving, and will be 90% invisible. At level 2, an alien will cloak within 1.5 seconds of not moving, and will be 95% invisible. At level 3, an alien will cloak within .75 seconds of not moving and will be 100% cloaked.
Focus: An alien will focus it's mind to be able to tell where to bite a marine at a certain point of time. It is amazingly accurate, each level will raise damage done by 50% and lower the RoF by 33%. This is due to the alien having to concentrate harder between attacks.
The other chambers don't provide upgrades. All of the upgrades cost 1 resource for skulks, 2 for gorges, 3 for lerk, 4 for fade and 5 for onos. If you choose to gestate to a different lifeform with upgrades already, the extra resources will be added to the cost (from skulk to onos, with 3 upgrades 12 resources would be added) or deducted (from onos to skulk, 12 resources would be deducted, which actually gives the skulk 10 extra resources to spend).
These are all subject to change, and are just ideas.
Also, the reason I suggested these ideas is because, in the next version, the devs wanted each chamber to be equally viable. Now I realize that, most likely, none of these ideas will make it in.
And, I would see MC being used the most out of all of these chambers first, due to their expansion abilities.
/Edit: Changed a few things on each chamber, removed "turning" from the SCs, made DCs more usable outside of the hive (with MCs), made OCs usable within range of a RT, raised OC cost, lowered OC damage boost, lowered StC range, gave DCs an umbra-ability, made MCs go to hives under attack (like now), buffed a few upgrades, etc. If you want to know everything I changed, just read it.