So it sounds like you are building a half stock smoothbore? Most of us on this site work off originals and do whatever it takes to replicate a close look of an original. That's where I get my inspiration.
Of course another approach is, "these are the parts I have and I want to build a gun." Whatever you decide you want it to work well, and so it does not hurt to look at originals. If you could tell us more about your build plans and go parts you have, we could help more.