ALL the bases need some fine-tune (alot), when you start game. What i've seen, some alien bases are prone to mass human rush at S1 (for example, Niveus.) And some human bases are quite prone too for mass dretch assault (they swarm all over the feet, get few kills, retreat and comes back as basi/mara/goon and finish the job done. good example, Tremor and ATCS).
So. Layouts don't concern much in 20 players and over. In smaller games its different though. Then layout should give meager protection. Humans can hop in if there is tube or 2 defending, or ret alone in corner defending nodes, without any sort of angle cover while someone in aliens took 3-4 frags and is normal mara.
And my final notes...
The building is always up to you.
If not.... get kills or defend for while.
And if no one builds, failure.
The End.