Different strokes for different folks. I agonized a long time on whether to add the 2x10 or the 1x15. Now I know this is stupid OCD, but I went with the 2x10 partly because the cab size is the same as the 500c. I know if I turned the 500c on its side, it would match, but then I'd have to move the Fender logo.
I once had a 2x10/1x15 rig that I really liked, so it was a hard decision. I wish I'd had the opportunity to try both configurations side by side. But, the 4 10s sound really good. If you like 10s, go for it. I doubt you will be disappointed.