the standard tyres aint all that bad as allrounders, they wear pretty well too, compared to all the other tyres i have tried. try something with longer spikes for the loose stuff, but be aware tarmac will wreck spikes... i personally havent found anything that works brilliantly on all surfaces, the dirt hawg buggy tyres are pretty good, but they ballon up too easily which is a shame, as they are dead sticky on most stuff.

try ebay, i got a load of very hard long spiked, low profile tyres off there for about a fiver a set, fine for bashing and cheap as chips. i think hpi do some good onroad tyres in 2.2", but they are pricey.

sorry i cant be off much more help, if ur running on very varied ground then its hard to comprimise. check that ur carb only opens to full throttle when the tx stick is all the way up, and feed the power gently - makes ur tyres last loads longer, but just doesnt look as impressive...

oh and in the wet.... well..... good luck!!