You can try Otocinclus. They are smallish fish that get along fine with your livebearers.
I am told they like groups, but mine have never seemed to even notice the others exist.
When you first buy them, they scarf down algae like they are starving... because they were... they are shipped that way. Once they finish eating all your algae, you have to start feeding them some extra... like zucchinni.
After a few months, you have a tank full of fat Otocinclus that eat zero algae and LOVE zucchini.
Seriously, they are cute little buggers, but they aren't much for working.
For bottom duty,
You can try one of the Cory species... they are about 2" and like big groups.
They are good workers, sucking up everything that gets missed.
But then they just poop it all back out.
Unfortunately, no, I am afraid Handfish and Hosefish still have to do all the cleaning.