Here are a few thoughts...
if you have a very wadeable river, the smaller one will provide good transportation from pool to pool so you can fish on foot (which I prefer). Small ones like the bronco (which I own) are easy to take down in fact it fits right in my truck intact. Don't use fins or you will regret it, just pull oars and fish from shore with these small boats. Anchoring a small boat in a river is a bad idea. Trust me.
If not, then you will fish from the boat - then you need a bigger one with the stand-up gear and floor. You might need a little trailer or spend some time assembling. A bigger boat can be anchored much more safely than a one-man craft in rivers but still requires caution over a 25 ft aluminum sled.
If you fish with a few friends then you need a larger raft or pontoon boat. I have seen giant pontoons that let two fish, but most often you just float the river and fish from shore.
You don't need to take out fishermen - just either let them know you are going to pass behind them or if you are joining the head of the pool pull out well upstream and walk down. In some cases you might pass the far bank well out of superman's casting reach but most often you would gently pass behind letting them know what you are doing.
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