you're quite welcome I tend to get on people's nerves, but I do try to be courteous at least
Anyway, I agree with what you're saying about Ben being an ordinary guy and resenting the weirdness. As for resenting the violence .. . dunno about that. He has clobbered a lot of people in his time, and I can't recall him ever talking about having a problem with that. Killing isn't the norm for him, but I think that almost anyone is capable of murder, especially large angry orange men with superstrength.
Granted, just because he did this doesn't mean that he was totally callous to it. The last panel showing him leaving makes him seem very affected by what he just did. If ultimate FF hadn't been canceled, we might see several issues of him being depressed and maybe feeling guilty.
As for your idea of Ben just releasing Namor and letting him do the dirty work . . . that actually sounds like a really good idea. Ben killing Doom himself still seems ok to me, but the Namor idea sounds more reasonable.