Here's what I'd do. I'd leave the dwarf gourami and platies in the 54 litre, get a few more platies (say around three or so), about 5 harlequin rasbora (or similar small tetra) and about 6 pygmy cories.
Move the angels to the 200 litre and add a couple schools of non-nippy tetras (neons, black neons, Von Rio), a school of cories for the bottom (depends on what you like and what color substrate you have...I have peppereds in my 29gal, an albino in my 55gal and a panda in my 20gL), and maybe a bristlenose pleco (albino or regular...or another similar smaller pleco).