I do my credit run in this order first thing after I log on: yeti, dragon, blackheart, ned, alligator, esmeralda, then last (in case I crash) in an empty instance I play my music mix, then remix it. It's a fast 170 credits that only takes a couple of minutes to do. I typically don't bother with the mansion ghosts, cause we all know what slow-pokes they are and I hate waiting for them.
While my main character is having fun in vmk, I open a second browser window and load vmk. When I find a spare minute, I put an extra character through its credit run on this second window. Lather, rinse and repeat for each character. Most days all my peeps get their credits, and by Friday can buy a new pin, costume part, or furnishing to trade to Lauralee.