My friend and I recently went together and finally got Descent (long story short we'd been looking for 2 years, and whenever we had the money couldn't find it in stock, and when we saw it in stock didn't have the money).
I'm fully intent on getting all the expansions eventually, and am about to start painting the figures in a while (another personal hobby in and of itself) but I know I'll want to play with adjusting deeper into the actual workings eventually. I've spent a lot of time looking at the various things that are available online since we got the game, The Warp's class system on BGG, the custom hero PDF, various scenerios, etc. I'm already looking to put some World Works materials to use for having a town adventure or two and some other little bits of stuff I have in mind.
What I'd really like to know is if there is any official or unofficial material for monster and equipment making, While the monsters and equipment in the game (and what I've seen from expansions) are nice I would love to be able to add a little more variety to the mix (god knows we have enough minis to do monsters and the cardstock and printer ink to make cards is fairly cheap) but there really isn't much reason for me the reinvent the wheel working out such rules if it already exists.