I did 2 years on a Hyosung GV250, close as a copy can get to the Intruder, on and after my Learners. Then I moved up to a Suzuki Boulevard M50, kept it until I went to Australia, rode a Honda ST1100 over there, and got another Suzuki Boulevard M50 with saddlebags, top box, heated grips, small GIVI screen and mirror extensions when I came back here. I've had her for about 3 years now.

So I'd recommend something in the Honda Shadow 750 to Kawasaki Vulcan VN 900 range, there's the Suzuki C50 and M50 plus the Triumph America in there. Just under that group is the Yamaha XVS650. They're all reasonable cruisers just a bit bigger than what you've been riding.

The best part about doing the research is kicking tyres around the bike shops and eventually going for test rides.