The moss balls are very cute :]!
CRS definitely be ok with excel. Just avoid overdosing and dumping the fertilizer on top of the shrimp! If you do inject straight into the soil you'll have no problems!
Pictures of the DW
Came up with a possible planting arrangement, maybe saggitaria chilensis in the very back, or anacharis, with dwarf saggitaria around the corners before the rocks. The anubias I ordered is a dwarf so I might stick that on the driftwood or in between the rocks. Kinda want a bit of red color but don't know where or which plant to get, also would be nice to have some small more textured leaves to mix things up a bit.
And pix of the driftwood:
My favorite one:
And a fts, because the frogbit has really taken off and is sending roots everywhere. There's also a heater in there now and a couple random plant bulbs.