Wilbers stuff is amazing value.
A few notes:
- Race Tech spring wouldn't change how the suspension feels beyond being either stiffer or softer than stock. Springs are pretty basic things, the magic of good suspension happens in the damping.
- To get the most out of that shock, it's probably worth doing a bit of work on the forks. At minimum, the oil probably needs changed (suspension oil breaks down faster than most think because it's being cavitated and forced through tiny holes thousands of times per ride).
- If you get nice suspension dialled in, it is a blessing and a curse. A blessing because you'll get way better ride quality and a more controlled feel in multiple circumstances. A curse because stock suspension will forever afterwards feel a bit crap, and you'll notice problems with things you didn't even notice before. It's not going to change your life like some will claim, but it is a significantly noticeable difference.
- Getting sag right is only the first step. Aftermarket suspension has way wider range of adjustment than stock, and it's much easier to get lost in the weeds of a bad setup. I would highly recommend at least taking the bike to a decent suspension shop and getting a solid baseline dialled in. At least that way you'll know what it's supposed to feel like for future tinkering. Getting a basic setup done is usually relatively cheap, too. Accelerated Technologies in Buckhorn is the best (semi) locally, but they're busy, so you'll have to call ahead to make an appointment, and they're hardly around the corner. On the flip side, there's some nice roads around there, and their dog is an absolute sweetheart...