After just getting the game I would definitely download and install the latest patch/upgrades program from here.
http://www.shrapnelgames.com/Illwint...DOM3_page.html
After that Id say that most mods would just make changes to the game. Not much reason to do that until you play the game for awhile and get the feel for what you like or dont like about it. Not much reason to make changes for what someone else didnt like. When you have played around for abit and have some things you would like to see different then we can recommend mods for those areas.