Sorry if this has been posted before, but I honestly think another 1-2 seconds on the altar turnover rates would be better. It seems that it is a bit too hard to defend a point and that if a summoner goes back to heal at all the other team can bum rush it.

Wards would probably help more than extra time. Early game the 90 sec duration can be penalty enough (having both alters ensures an 800-1400 gold lead for the opposing team by the time they hit lvl 3).

Now imagine having Twisted Fate on the new TT map. Vision, teleport, even more gold for the team. Have fun~