40 G high (looking to add more fish any ideas?)

i currently have two false perc clowns one 3 line damsel who is young nad not ever aggressive yet. 30 pounds of live rock 40 pounds of live sand. for cuc i have some blue leg hermits and some red hermits and a couple kinds of snails. i'm looking to add more fish but i'm not sure what to add that would get along well. all my levels are great 0 amm, 0 nitrite, 0-5 nitrate its hard to tell with the color cards. i do not have a sump i have a hob bubble magus skimmer that works amazingly well but overflows at times :/

help with fish ideas