My sailing background is somewhat similar - only much more time on the Great South Bay than the Sound. When I got back into sailing after many years, I spent a lot of time looking around and sailing various boats. The larger and older keelboat designs didn't do it for me. A little too slow, too much overhead in keeping them functional (cost, time, things that break, etc.), and, for me, not enough fun. The VX-one was/is a hell of a ride, but it was too aggressive for the wife, and not the best or easiest way to get back into sailing. The U20 was a great compromise. It's quick, nimble, and with enough breeze, will get up and get running. If you push it, you get rewarded every time. If you dial it back, you have a stable platform for you and some friends to enjoy a few beverages or grab a snack as you cruise. The one thing I note is that even when I'm "taking it easy", I seem to be passing the other 20+ foot boats in the club.
All of the systems are simple and straight forward and maintenance is relatively low. Others, with greater skills/experience, may disagree but it's not the easiest boat to single hand. However, I can take complete newbies out and get the boat moving 10+ knots downwind without any drama. Again, others can probably do this singlehanded, but I'm not there yet. As long as I can find a semi-protected area to douse the main, I'll go out singlehanded in up to 15 knots of wind. Reefing the main is essential for me. Others may not need to, but keeps the boat more controllable and balanced for me when I'm out by myself.
There are probably better, cheaper, easier solutions, but I purchased this to hold the tiller in place and it works reasonably well.
https://www.fisheriessupply.com/rwo-marine-tiller-lock-19-27I bought it on some kind of sale for <$50. The current $115 price seems ridiculous. On the same site is this one:
https://www.fisheriessupply.com/davis-instruments-tiller-tamer-tiller-stabilizer-and-lock-2205for $27 that's probably as good or better.
Also, I'll bet that $5 worth of shock cords will probably do fine as well, but I haven't experimented yet.
The other thing to note is that where I sail, there's typical 2-4 waves/chop and a decent current. I'm going to guess you don't have to contend with that on the lake which should make it easier.
Good luck and go with the U20. As others have noted, it's a great boat and this community is available and supportive.
-RobC