A theme I've been noticing in the posts in this forum is that currently the Onos is not awe-inspiring enough. The appearance of one isn't striking enough fear into the enemy. This is a fair enough point, because for the game to remain balanced, the marines would need a way to deal with every alien becoming one at the same time.
Well, what if that wasn't possible? I'm not entirely clear on how the mechanics of it would work, but the general idea would be that for every player that becomes an onos, multiple other players would have to give up the option to also become one. Once the maximum number of these creatures is limited to a percentage of your team, you have a little more room for increasing their power and survivability.
The question remains though, how could this limitation be implemented in a meaningful and intuitive fashion? Perhaps multiple gorges need to "build" an onos egg before a player can merge with it? I'm a little stumped on this one, so I'd like to hear some other thoughts on this.