Currently I have 12 adult breeding angels and 4 pairs of breeding rams in a 220g planted tank along with a pretty good size Longfin Albino BNP and I have never had issues of anyones eggs being eaten by the BNP. One thing that helps alot with Pleco's in general is to offer them veggies and/or algae tablets 2x a week. All my various species of pleco's in different tanks especially like cooked, deshelled peas and soften zucchini. By feeding them at night a couple times a week tends to keep them more satisfied and less likely to get into mischief.
I'd be careful with the pleco/puffer mix. It is pretty much going to boil down to the personalities of the puffers.