I have issues with legroom on our 390. I'm just over 6' with very long legs, and only the inside of my knee bones touch the sides of the tank cover. Which can be a bit painful in jeans, not so bad in leathers. The 2017 tank cover seems to have a bit more room there.
Some rearset peg assemblies would fix that, although wifey might not approve. Folding pegs would be a requirement. I made some simple rearset plates for the assemblies on the SV, which is also really short on legroom, but the 390's plates are held by the swingarm pivot bolt like the FZ-09 I worked on. A bit harder to R&R those.
Lighter makes it righter!