Would a few Hatchet Fish work there? They definitely inhabit the top and are small.
Not a bad idea, but they are jumpers, so you'd need a lid on the tank or you'd start finding carpet surfers.
Yeah, and to be honest, hatchet fish have always kind of scared me. I don't know why, but they freak me out.....

I wouldn't say scared, but I must say I don't like them either.
Hmmmm...I think you've sold me!

one thing though - I've watched some videos and done some reading and it seems like this fish is a mid-level swimmer? I've already got 3 of those

sorry for being picky...
Where could I find Espei rasnoeas? They're not sold at my LFS
Sorry, can't help you there.
Try asking the LFS to orders them.
Yes, actually you're right. They are mid-swimmers, but you'll find there are few species that are strictly top level swimmers, bu mine do spend more time in the higher part of the tank than in the lower part.
Cardinal Tetra will do far better than Neon Tetra at the high-end tropical temps (27C plus) needed for your Rams.
I *love* cardinal tetras. I was thinking about a few of those as well!
I have a shoal of cardinals in my bigger tank, and they are not much of a top level swimmer fish. Also they are larger than espei rasboras, you'd be able to fit fewer in. Also, before cardinals I'd suggest rummynoses. They are tight schoolers an are very active. When you have a 15+ school they look BEAUTIFUL. Pity you can't fit that many in your tank