In my experience I’d say they should be good with the amount of hiding places you have but I’ve also never kept rainbowfish.
My betta is incapable of taking down the adult ones as they are so large but the juveniles you will get may be more susceptible.
The caveat that I will note is that they are great escape artists and love to carpet surf. A lidless tanks means that they may escape into a more terrestrial environment.
James_bong42 
Mature angels will eat or at least kill amano shrimp. XXL ones might survive for a while if they hide, but they won’t survive indefinitely.
In my experience I’d say they should be good with the amount of hiding places you have but I’ve also never kept rainbowfish.
My betta is incapable of taking down the adult ones as they are so large but the juveniles you will get may be more susceptible.
The caveat that I will note is that they are great escape artists and love to carpet surf. A lidless tanks means that they may escape into a more terrestrial environment.