I gave up on the idea of buying the D2 expansion some time ago even though I was not aware that the cheating problem was as bad as you are saying. I haven't played a party game on the realm servers for quite awhile so I didn't really know that was going on.
My major complaint with D2 (aside from the fact that the realms STILL get overloaded) is the fact that they effectively removed single player by taking out the save game option. That one thing, for me ruined D2!
John-SJ