I'd look at why the painting has meaning to your husband and build a gallery wall around that. Is your husband a veteran? If so is there any memorabilia that he might want to display? If it's the patriotic theme you could find a flag or other items to display in that vein. Or you could riff off the hunting theme in the artwork if that resonates with your husband.

The painting is a bit small, but not a lot small. Two smaller items on one side, or four even smaller items with two on each side would make a nice grouping.

Great ideas on the grouping. Yes, my husband is an Army Vet. I just don’t want to relive my late ‘80’s decor of oak shelves and crafts. Would you suggest painting the frame?
Thanks for the help!

I think the frame is fine.

I'm sure there's a way to display items without 80s-era oak shelved (there were a lot of those in my mom's house). I suggest you brainstorm with your husband, if he's game, about what items he might like to display, and then you can come back here for concrete suggestions. A shadow box is a nice way to display small 3D objects, for example, without an oak shelf in sight.