I agree -- I think having the mroe artistic angled photos as additional photos but maybe not the main photo is the best idea.
I like the wood background with frames when the frames are a different color, like here:
https://www.etsy.com/listing/236331744/personalized-dog-picture-frame-with-name?ref=shop_home_active...Having the black frame in between the wood background of the picture and the wood inside the frame is nice (along with the black accents in the frame). The contrast is nice there.
Your first four items (the 'featured' items) like the one below have natural wood frames, though, and I feel like the background wood + the wooden frame + the wooden pieces inside the frame kind of bleeds together and it doesn't necessarily make the item itself 'pop'.
https://www.etsy.com/listing/230717003/unique-guest-book-alternative-wedding?ref=shop_home_feat_1Maybe you could photograph the natural wooden frames on a slightly different (lighter or darker or more weathered) wooden background so that it blends in with the background less. Or try brightening up the photos, as that may help!