Greenwood's Pike is easily one of the best things in either movie BUT his lack of resemblance to Hunter's--in terms of age, temperment and appearance--is one of the many, many things that makes me view these movies as straight-up reboots, with the alternate timeline stuff as a fig-leaf of sorts as well as a way to shoehorn Nimoy in.
As such, I think it makes better meta-narrative sense for Greenwood to be Pike rather than, say. April. Pike was the cornerstone to one (or two, depending on how you want to look at it) of Trek's better and better-known episodes. April was in a little seen and forgettable episode of TAS. Pike is a better nod to semi-serious fans, the type who know trek pretty well but don't talk about it in online forums.