This is actually pretty good. She's a lot better in a Isekai then a normal story for some reason...?!
At first I hated this but now I see the charm.
 Honestly, I'm still very confused. Where is the Author planning to go with this?! 
For once I wouldn't mind the polygamy route since I really like Kana. The gnome girl cockblocks him too much though, shes really weird