First seats seem to be fairly easy to fix and most serious riders I know have purchased an aftermarket seat no matter what bike they ride.
Dual sport bikes like the KLR are said to be easy to lower with a linkage change. May even be available from Kawasaki, I know Suzuki sells one for the DR650.
The GS500F (faired) should be the same bike as the GS500 only with extra plastic. It may look like a sport bike but is actually a standard. The Ninja 500 and Ninja 250 are of similar style though I found the GS500F to be the most comfortable in a seat test.
I also really liked the feel of the WeeStrom and Versys. These seemed to be nice general purpose bikes. They look “different” but thats part of what I liked about them.
I’d agree with others about the Blast. Its kind of an orphan with the demise of Buell and was considered good only as a beginner road bike even before it was canned. I think you may find it a little small also. In this class of bike I like the TU250x and Ninja 250 much better.