Everyone liked the xenos getting strong aspect.. but no one liked waiting 10minutes as a T3 to be "viable". Or to have to be forced into a Weak T3 role because we "need a prae"... losing all your maturity.
Personally I think the problem with the marines is the same as the Xenos used to have.. they just have no time to build defenses before the hive rushes. Staff shouldnt have to step in and "stop" one side or the other.. the game should be tweaked so that doesnt happen as often.
To slow marine rushes.. Xeno defense building should be free for X amount of minutes.. so you can actually build up the cave and nests.
To slow xeno rushes.. part of the map should be on "lockdown" prior to marines pushing some kind of a button. For example LVL, the entire nexus was "emergency locked down" with unmeltable shutters/walls. The xenos cannot get in until marines remove the lockdown (or it automatically removes like at 12:30).
I mean this is why LVL is one of the best maps in a lot of people's eyes (mine included).. the fog allows both sides to skirmish a bit.. but provides some time for both sides to build up a foothold.