If you could give any Pokemon a Mega Evolution, which would you choose?

I have a sort of rationale for this, which I outline here… basically I think mega evolutions should go to Pokémon 1) who are weak primarily because their stats are low, and 2) are unlikely ever to receive a conventional evolution.  Suggestions I put forward there are Ledian, Bibarel, Delcatty, and Plusle and Minun (disclaimer: I avoid spoilers on new Pokémon games, so if one or more of those Pokémon is getting a mega evolution in Sun and Moon, I don’t know and I don’t want to).  We could also add, perhaps, Seaking to that list, for most of the same reasons, and maybe Zangoose and Seviper (whose base stats are high enough that they seem unlikely to ever get regular evolutions, but not high enough for them to actually do anything).