yeah man I've seen Valhalla and read vinland saga, great stuff. i think I would focus on fenrir and
Jörmungandr teaming up with a mayan jaguar demon and rakshasa. The asguardians will be more like tron-ish computer programs/automatons. Valkyries will totally be in there on the front lines fighting bone men.
This is all world building for the comic idea. I post more stuff on the subject on my tumblr:
spaghettibastard.tumblr.com/hopefully ill have a comic soon, if I cant get it published I'll make a webcomic, either way I'll announce it here