I felt the same way about Valiant Hearts but decided to stick with it through to the end. I gained nothing by finishing VH, but wanted to tell you that the second half of the game is entirely pointless. You're not going to be missing much.
I found the portrayal of the enemy characters equally irritating. The strangest thing I took away is that, for a French development team, I thought they would understand or be aware that the German leaders during WW1 were considered to be as evil as Hitler during the post WW1 era, and it was a combination of being overshadowed by the events of WW2 and Nazi propaganda framing the WW1 leaders as buffoons that changed their reputation from blood thirsty, warmongering tyrants to idiots in pointed hats.
By the end of the game you're are walking over piles of dead french troops, with the in-game art made up of limbs and torsos. You're not missing anything by bailing out.
PS: hope this was coherent. I've just woken up.