upgrounds are usually electric only or a 10hp limit (for the most part)
erie i would go with the biggest the boat is rated, but you could get away with smaller on relatively calm nearshore water. just my .02
I have a 16' Lund wc 16 dlx. Have a 9.9 on it and with 2 people can get on
plane and achieve 13.7 mph gps. The 9.9 is great on gas, rarely use more
than 2 gal per trip out. Exception was spending the whole day w/4 adults
at St. Mary's last year just boating around the lake, used 5 gal. that day.
Also have the ability to pretty much use about every lake in the state.
That said and done I wouldn't mind finding a good quality used 20 or 25 for
those rare occasions (Lake Erie shore line)
Man you want what ever the max HP rating is on your boat.You can always add electrics for the res.I run a LUND REBEL with a 50 Evinrude tiller.Came back across Erie from nine miles out at 27mph.yesterday and that was with a full livewell and a big dude sitting in the middle seat.Mother Erie,you just gotta love her!!!