Sorry, guys! I was at work. 

As Demon stated before, yes, we will have ages. As stated in the first post, Pokemon are expected to be at their final stages by their mid twenties to early thirties. Stats will also be used, but it's mostly just to compare characters in PvE and PvP scenarios. 

As for the rarity of Eevolutions, I believe that Demon and I settled that evolution stones are pretty rare. There will also be dark-based stones that will let Eevees evolve into Umbreon, sun stones evolve them into Espeons, etc. Since these stones are so rare, they are only used in certain rites of passages and are perhaps protected by legendaries. The short answer is that you won't be seeing Eevolutions bounce around everywhere, and seeing one might surprise some. Pokemon that depend on the stones in order to evolve are also pretty rare, but that doesn't mean you can't make em.