@WUBBAWUBBADUBDUB77 Hahaha... I've had the same issue with the terrible townie outfits. I hurts my eyes. I had a retail store and finally hovered over the townies (same ones come in all of the time when you own/run a store), got the townie names for the eyesore offenders, and hunted them down in the unplayed households in the game and gave them a makeover. ;)
As far as eliminating townies, All you need to do is look for them in the game-save's households. Most likely they're in your 'Manage Households' unplayed households ('Other Households'/'Not in World') vs. played households ('My Households'). I've given these sims makeovers, and occasionally re-aspirationed them if they work in my store or restaurant. ( You cannot change the traits without a cheat or a few other more invasive methods.) I've also been known to delete some with the 'evil' or childhater trait for specific situations, and those who frequent my store or restaurant with the 'klepto' trait. I had one guy that stole a painting off the wall (while I watched - not sure what else) and wouldn't leave the restaurant and would not listen to being asked to leave. I had to have 2-3 different sims fight him, and he still didn't leave. My solution? I hovered over him, got his name, hunted him down in the game's unplayed households, and deleted him. Problem solved.
You should probably take the time to make some 'replacement' sim households - probably 100 or so, if you're deleting all of the pre-made ones. Or you can just create a new one for each you delete.
Hope this helps! Have fun!