Re: help me choose 12-14 foot alum boat.
You want a boat like mine.

You can see it in my avatar.
There's a bit of wood in the transom, but other than that it's pretty much failproof. Rivets can get leaky, but they can be rebucked easily and even when they're leaking it's not a big deal. Mine leaks some but I just use a cup to bail water outta the back every few hours. Mine has no floor other than the aluminum hull and has 3 aluminum benches stuffed with foam so hopefully it won't plummet to the bottom if a lot of water was somehow taken on. If you have a fancier boat with a wooden deck and seat structures things get more complicated, of course.
My dad surprised me with a new 15hp 4 stroke Mercury motor for my 10 year job anniversary (he was ticked that my work never even made mention of it...

) and it really screams with just me onboard. I've clocked 29 which feels really fast, especially with any chop!
I had a 6hp '72 Evinrude that was a solid little motor despite years of neglect but I'd go for at least a 9.9hp or 15hp in a 14' hull rated for 15hp. (like mine) It was stolen a few months ago and I still miss it and had plans for it to go back on the 14 footer when I got a bigger hull and would use the new 15 as a kicker.
Where are you at? We'd be happy to look over craigslist ads etc. with you to try and find good candidates. Or post pics of unlisted boats for sale that you can find locally.