+1 except for the hatchets, because they are, IMO, a bit finicky for a beginner, and rummy nose will fill in as dithers/top dwellers.Never had an issue with angels eating otos in 30 yrs....
I'd do two groups of 6 cory, different ones....
10-12 cherry barb or rummies.....
and 6-8 hatchets for the top...
and a BN....