I disagree with the idea of removing the altars. The altars add strategy and add one way of forcing a fight outside of the lane.
I love the idea of pushing the lanes and then running to the altars when the enemy if fighting the minions, it makes total sense to me.
Regarding buffs, you say there are no buffs in the map... well, there is Vilemaw which gives a great buff.
I do feel though that the inner defense near the Crystal is a little bit too low (Only 1 tower), although thanks to it I've participated in several great game endings with both teams fighting around the Crystal to destroy/defend it.
In this map, once you destroy 1 inhib there is almost no turning back. The super minions will overload the base, and the team won't be able to escape from there. That also implies that team will always control both altars, and possibly also the Vilemaw buff... turning it into a no-comeback situation.
I've never participated in a comeback after 1 inhib down. What's your experience on this front?