Personally, I don't think the style of boat much matters as much as how you rig it out. On Chickamauga Lake I see EVERYTHING from fishing kayaks, up to $60,000 bass boats out crappie fishing. I always smile a little when I see a $60,000 Triton or Ranger rigged out with crappie rod holders fore and aft. But hey, they catch crappie... and you can do the exact same thing in a 14 ft. job boat.
Now I fish out of a 17 ft. deep-v (G3 Angler 170). I really like the deep-v. On big water when the wind gets up, the deep-v handles big waves MUCH better! A flat-bottom will beat you to death. But I fished (and duck hunted) out of a 16 ft. flat bottom for 25 years and it served me well.
If you're doing everything (fishing & duck hunting), that would probably be my recommendation. A 16-foot foot flat-bottom or semi-v. And actually I think extra width is very important. I'd say a 52-inch beam minimum, even up to 70-inch beam (which is what I had). The extra width really helps on stability and gear stowage. I ran a 40-horse Mariner on mine (although now I'd recommend a Yamaha 4-stroke).
I bought the plain aluminum (then painted it camouflage), but I added a false floor myself. I could put carpet down easily myself and the false floor helped hide trolling motor cables, etc.
Mine had a livewell, but most livewells in aluminum jon boats really don't perform very well unless they are WELL insulated and aerated. If you're mostly worried about crappie, I would always just carry an ice chest, and put them on ice as I went. I'd do that even with the livewell because as water temps would warm, mine just wouldn't keep them alive well.
Again, that boat served me well for 25 years doing some hardcore fishing and duck hunting. I had to upgrade when I started guiding, but I often wish I still had that old 16-foot jon boat back.
I hope all that is of some help.