I have ottos (which are not bothered AT ALL), baby bristlenoses (adults DO get harassed) and shrimps. My tank is very heavily planted tho and its 5 puffs in a 20gal tall. I also have SAEs with mine (since they were small) and they get nipped occasionally but nothing bad. Mostly everyone gets on SO FAR.
The thing is, DPs might be fine around loads of kinds of fishes, but then one day they could just change and become nasty. You have to be prepared for this and able to remove ANY tankmates to save them if necessary.