3 shrimp in a 1.5g? They could live their whole lives in there. heh Smart thinking on your quick set up. Sorry about your TOD.
I'd keep them under quarantine for a month if planning on moving them. If not moving them, add a seeded sponge filter and you are good to go.
The biggest challenge with small tanks is to keep on top of params. Evaporation will play a huge part in prams changing.
My favorite eye color on neos is green. I've been waiting for someone to do a strain of specific neo eye color for a long time. Such a simple idea, yet noone has created a strain yet- which has surprised me.
Yes, I have also seen white.
They'll throw them occasionally. If you want classic rilis, just end up keeping more and more of those and less and less of splotched, or sort them out into different tanks/compartments.