They've changed it back to more fast paced leveling in .914. However, non CHampions (so trained units and summons), only receive half the base XP for each fight.
However, they have coupled the increase in speed leveling with good items being much rarer than they were in .912 (at least in the couple of games I played this weekend). This meant that I was able to have more abilities (which is cool!!), but not get superpowered till later in the game where the techs for the trained units are able to cope with it a bit better.
Pure mages can still be OP very easily though, even without the cool equipment. But a pure mage witll only be OP vs non champions, or champions of significantly lower levels due to debuffs not being as easy to apply (you only gain 2 mastery per level, with 60? base mastery. therefore before modifiers, equal level champions the mage only has a 60% chance of debuffing the other.
Overall I like. And by the end of the game when you are picking up epic loot, it is AWESOME