I use it sparingly and I'm trying to reduce my dependence on it to start off with (though I use the debug tools to add units because I don't like seeing more than the map I can see in game because I also like to guess my opponents as I explore and find them. I can usually "feel" whether Justinian is out there with 100% accuracy...). I usually start with two settlers, two workers and two spearmen (in addition to the things you start off with anyway), and I'm now down to one settler, one worker and one spearman and wondering which to eliminate next so I can begin to play properly.
I used to go in and add horses/copper outside the BFCs of any cities if I didn't get them when I researched AH or BW, but it is now making the game a bit samey to do that so I'm trying to wean myself off my "starting package" gradually.
Once I get momentum going I find that I don't have to do anything with debug tools or Worldbuilder...I'm afraid on a lot of games I cheat like crazy because for me a game is something to explore rather than try and beat the hard way, but the really impressive moments come when you win despite the odds (like on Icewind Dale when my mage ran out of spells, all the other characters were magically asleep or held, and she killed the last wight between her and complete game-death with a +1 dagger going toe-to-toe with it...classic moment where the entire game hung in the balance and I didn't even bother to cheat because things were going so close...).
In Civ I am regularly beating Warlord but think I ought to reduce my dependence on starting with a huge advantage to see whether it is me being cheaty at first that gives me such a huge edge or whether my strategy based on that starting package (essentially (Mysticism->Meditation (found Buddhism)->...)Warrior->Stonehenge->Great Wall in first cities and Warrior->Barracks->... elsewhere is sound without the bonuses I give myself initially.