It sounds like you want a boat that doesn't really exist to me. Or more accurately, you want a boat that does what several different boats are designed to do.
First off; and this is important. Class II IS whitewater; and Class III is pretty serious whitewater. Inflatable boats that are capable of motoring upstream in class III whitewater are not common (I've never seen one), and are VERY expensive and have many times 10 HP to do so. So there is that.
It sounds to me like you want a hybrid of a Rigid Inflatable boat (RIB) and a raft. But I don't really know if this boat is real. Rafts do not really go up on plane, unless they are rigid floor, and even then they don't do it that well (in my experience). RIBs don't really tend to have oarlocks at all and are typically unidirectional - and rafts that have motors don't plane well...so your idea may be a non-starter.
Depending on the rivers that you are fishing - It sounds to me like you want an aluminum jet boat, not an inflatable.
but can you see its opposition | comes a-rising up sometimes | that it's dreadful and position | comes blacking in my mind | ....and then I see a darkness