What should I change this year

I would say this depends on two different directions. Are you just trying to go faster, or are you trying to be more consistent? If your into bracket racing. Then consistency is the directions to spend. Alcohol, tranny upgrade, engine mods that get you closer to the middle of the road of tuning performance. If your into grudge match racing? Then speed is where the money goes. First start with cheep. Dump worthless weight. Then move on to cost items. Steel to aluminum, glass to lexan, hoods trunks and bumpers to fiberglass, get down to the bones and dump some weight yourself if you need (that's a joke) but..... Also make sure your running the best gearing setup for your power combination. Get to that - crossing the line, all in, nothing left on the table power band thing right. Then go after the really expensive stuff. If your chassis can handle more, and the pavement will hold you. Add, Add, Add. Power, Power, and torque. If not, upgrade the weak links and move forward.

In short. Bracket racing - middle of the road tuning performance - consistency, then more as your bracket allows.

Grudge racing - dump the weight - gearing - chassis - power and torque.

Remember - sometimes you have to jump around and go back. Changing the power band can change the gearing again, or maybe a tire size change will cover it.

Note: I can explain my middle of the road tuning performance theory if needed.