You’re not alone. I came to the same conclusion. I’m 6’0 205, and I’ve been researching what my first bike will be. I narrowed it down to the SV 650, too. I’ve been sitting on a lot of bikes, and for me the deciding “comfort” factors have been seat height and position. So far the seat height and the upright position of the SV has felt the best for me.
You might also want to consider the GS 500F, supposedly a good beginner bike. It’s more ‘sportier’ than the SV, but the position isn’t so bad. It has about the same seat height too. I felt pretty comfortable sitting on it. Depending on the year, you can get it with a fairing or naked. The GZ 250 wasn’t too bad either, but it’s lower, felt smaller, and seems more cruiser than standard (despite how Suzuki classifies it on their WS). I like upright-to-slightly forward positioning. I felt big and uncomfortable on the Ninja 250.
I’ve been concentrating mostly on Suzuki, because Suzuki bikes seem to show up regularly on ‘best beginner bike’ lists and recommendations. For example, CycleWorld’s September issue has an article on it, and IIRC, nine bikes are on the list, including both the SV 650 and the GSX 650F.
Good luck to you!
ray