Block Combinations

Hey guys so I am asking for advice on which blocks could fit together well. I have a big room in my singleplayer room that I want to make a design for but, I just can't find any good blocks really. I started off with using dark oak logs and spruce slabs and I thought it looked good, but I need another block to fit with them. So now I'm asking: Which blocks fits well with those? (doesn't have to be wood)