Not that it matters, but for your info the XT is M770 and the XTR is M970. Either way, they use the same bcd rings. You can use whatever rings you like as long as they are 4x104bcd. If you're sticking with a multi ring setup, then I would replace it with a matched middle and outer ring set. The granny doesnt matter what you go with because you dont have ramps or pins on the inner ring. I doubt highly that you even need to replace the granny gear.
Edit: Right, suggestions... I think Shimano rings shift pretty well. I"m not crazy about truvativ. I've had decent experiences with Race Face. Blackspire is one to look at as well.
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