Jungle creeps evolving

This has likely been thought about or discussed before, but I'm not positive...

I think jungle creeps staying the exact same over the course of an entire game can get rather boring. Does anyone (junglers mainly) agree? I think the jungle creeps could be more menacing and more of a threat in later stages of the game. I understand that this would entirely reshape how the game is played, but is it a good idea at all?

Now, jungle monsters are barely noticed past level 13 or 14. ("Oh look, wolves are up might as well kill them in 2-5 seconds... yawn.") They are killed instantly and give the same amount of gold every time. Wouldn't it be more interesting if each creep "evolved" after a certain amount of time, one by one? I think jungle monsters having their own unique abilities can be fun. They would evolve to look cooler and bigger. I see red and blue monsters, and crab staying the same. I also think a jungle monster that hovers with wings would be cool.

The wolves could evolve first, looking cooler, doing more damage, and their gimmick could be aggro-ing on sight. Gromp could also change its form slightly, and have a tongue attack ability like kench. Krugs could merge into one large krug, gaining an ad shield, offer a new buff when killed giving defensive stats, and a shield aura that activates when close to allies. Players and junglers would have to coordinate more by coming close together, but the subsequent shield would be powerful. No ideas for the raptors yet.

Is this idea of evolving jungle monsters any good? I think it can be done, if done right.