all tetras are fin nippers..but in the right school ling size, and tank size, they usually dont bother with others...both of which you have.maybe even add a few more to your tetra school unless you plan on keeping yoru common plec rescue? ..the only worries I would think would matter is that your angels may think of your neons as a snack...but if they are juvie angels, or adult angels with a ton of plants for the neons to get away, probably less likely to happen...I think it would be a great addition but you are going to have to keep an extra
water change in there or so, as you are at the max bioload wise with your rescue
