Fish are less likely to go after clear shrimp and shrimp that blend in... i.e. brown. Shrimp that are more colorful and stick out like a sore thumb are more likely to be preyed upon. If a fish is a true hunter though, it wont matter what color the shrimp is, they'll hunt them down.
If you do in fact have Neocaridina, then a Caridina species, such as tigers, wont mix with your Neos if you do end up having them together. (not completely true, but rare for the two to hybridize?) That way, you are more likely to keep the prettier looks. Less "culling" is also necessary. If you were to get a colorful Neo, then some amount of culling (removing from main population) would be required in order to keep the bright, strong colors.