I have to agree both will work but look at where you are going to be bowfishing. Those barges are hard to get into tiny spaces if your in back waters or flooded timber but would be ok for more open water. A good wide flat bottom or semi v are very stable and allows you the best of both worlds
Width is more important (IMO) then length a lot of times. I started the same way with a 12 foot boat, then a 16x48 and now a 20'x60" and while it is plenty big enough I wish I would gotten the 72" botom.
So what ever you choose get the biggest you can, save yourself the hassles of upgrading to get there later.