I don't like it. Having your rax taken down basically limits an entire lane from being farmed nearly as well, on top of more powerful creeps. A comeback isn't dependent on the fact that the creeps in the rax'd lane don't give as much gold.
A comeback is dependent on either outplaying your opponents as a team or outcarrying opponents using gold acquired from the other lanes. Disregard the rax'd lane if you're carrying, it's worthless, let the support push it back.
What I'm trying to do is emphasise the former.A comeback is dependent on either outplaying your opponents as a team or outcarrying opponents using gold acquired from the other lanes.
Most games end up incredibly one-sided, which is much duller than it needs to be.
This is because one side typically has:
1) Major levels advantage
2) Major farm advantage
3) Map domination advantage. Mega creeps push losing team back into constant defending, winning team can farm/kongor/gank/push at whim.
Skill drops out of the equation at this point.
#1+2 can be changed through a mechanism similar to that which I described.
#1 could be reduced through making the levels less linear wrt experience. In other words, make levels 1->12 easier to achieve but 14->25 more difficult. As such, the winning team will have less of a levels advantage.