What to do - thoughts appreciated

[subman]

The small amount of LR doesn't really matter, as long as your livestock is still small. I'd treat it like a 20g tank for the amount of livestock for stocking.

I like adding fish first, I find them a better sign of tank health in the beginning. I like clowns as a first fish they are hardy, captive bred and are a staple in any marine tank. I wouldn't be afraid to add a mushroom or inexpensive poylp as well.