Choosing Meredith as a name doesn't strike you as a bit odd, given his history? [I love it when parents do themes, or sound-alikes, and such, so all "M" names are great to me XD.]
Good ole Meredith is the very reason for that name. (◡‿◡✿) I have, uh... a lot of feelings about Cullen's relationship with Meredith (not like that, I mean generally as a friendship, a mentor/pupil relationship, an authority figure, even a parental figure in the absence of both their families), and they are complex and conflicting, and the way I interpret Cullen, he's capable of discerning the actions from the person and acknowledging that Meredith the person who was scared and overzealous but not unjust was one thing, and Knight-Commander Meredith who succumbed to red lyrium-induced mustache-twirling madness was another. The name is supposed to be about preserving the memory of his relationship with her in better times, giving her name a clean start in a place where he can hold no resentment over it, only love for his little Meredith noodlet who will be the best Meredith in all history, etc. It's all very convoluted and headcanon'y and bittersweet, as my interpretations usually are. 
Meredith also means "guardian of the sea" which my sea-loving Trevelyan who misses Ostwick very much just loved when Cullen suggested it.
Anyway, yes, I love the inherent cheesiness of parents doing themes with their poor kids' names too. The story behind the M for Cullen's noodlets is a bit convoluted too, but not gonna lie, all my headcanon babies for Anora and Alistair start with a C too just because.... cheese. 