Free stuff
Adjusting levers and bars to fit me as good as they could. Ease of use.
Fiddling with suspenders until happy (this is an ongoing thing...)
Easy Stuff
1/8th turn Quick action throttle; so much easier.
Solid mounted and raised rider seat. More comfort, better feedback.
Harder Stuff
Reduced offset yokes, I like the 'extra turning' they allow.
BST's. Hard as in hard to justify. Awesome, but in one hit its a lot of cash.
Boring stuff
Riding courses. Whilst war-stories are significantly duller, I find not hitting stuff to be, on balance, a good thing.