I think that taking your rig into the field will tell you what things you need the most. If you can't hold anywhere close to the target, then you'll possibly need a better portable bench and rest or bi-pod / rear mono assembly. If you can hold but can't hit maybe you'll need to work up better loads or have some work done to the gun (or both). If you're grouping at distance and can't hit when the wind picks up or the weather changes, you may need a better wind meter ( FYI, I'm using the 4500 NV, I got a good Ebay deal on one), or you may need a better program on a pocket PC. For the PC, I bought the Nightforce program and a pocket PC that would support it. That's all I wanted the PC for anyway. Once you can hit at distances that your range finder won't read to (or won't read accurately to) then you can look into a bigger range finder.
You do realize that then your caliber will be holding you back and you'll have to step that up to stretch things a little farther?