Need some opinions on a 15 foot aluminum boat with an Evinrude 50hp prop.

Here's what I know:
Late 70's Semi V riveted hull
50 hp Evinrude w/ controls
Forward steering wheel
Windshield
Fish finder
EZ loader trailer
Never been in a river
No dents
On it's 3rd owner
Always garaged

I want to use the boat for areas like the Snohomish, Sky and not too far out in the bay. I'm not looking for a boat that can do it all just something that can get me into silver's, King's and Steelhead.

Being that it's riveted what are some of the problems I'll encounter if any?

What's the difference between a welded and riveted boat? i.e. handling

For those of you that fish the Sky during higher flow will I be able to get around with the prop out back?

I've never looked into jets. What a rough cost to convert a older prop to jet? Is it worth it?

Anything else I should look at feel free to inform me. Any questions ask away.

Thanks Rick