Im more curious about the biggest bang for your buck. What things are going to make the bigest impact on your riding.
BST wheels will make a big impact. Its right up there with suspension. Its so good that some races ban lightweight wheels.
For me the brakes on the 899 is probably the worst part of the bike. They are not what i like. The brakes are by no means subpar (some people think they are because after a certain riding limit they actually hold you back). I prefer brakes with a different feel. I think the reviewers say they are using the same brakes so this may be the first mod before the wheels.
Next is probably an autoblipper by tuneboy. I hope they make one for the 959.
Depending on clutch feel, a slave cylinder.
A upgraded steering damper.
i haven't gotten to the point of outriding the suspension yet so that would be last for me. ohlins fgrt, nix30 cartridges/ttx, or Mupo K911/ab1
Going to try the Pirelli Superbike Pro 180/55 on dtc2.
Contact Yaman to see if the rapid bike on the 899 can be fitted to the 959.
This is probably my list until something pops up down the line.