Well, is yours a tall or long tank? This can affect how many fish you can keep and the best ratio of top, middle and bottom dwellers.
Perhaps a school of hatchet fish for the surface, a couple tetra schools such as the rummy nose, neon, cardinal, black neon or glo light.
If you're outside of CA you could look into glo fish as well, they're genetically engineered zebra danios altered to be super bright and colorful.
Or you could have a school of regular zebra danio, or perhaps some guppies, harlequin rasbora, thread fins, platy's or mollies.
For the bottom you could do a school of cory cats. I prefer the panda or jilli as they reach about an inch were as others can get nearly 4 inches. Or maybe a school of khuli loaches, they can be kept in singles but display much more 'loachy' behavior in groups. Or maybe some shrimp like the cherry shrimp which comes in reds, yellows and blues!
You could also get a sucker fish for the algea, there are some dwarf species like the bushy nose or rubber lip that are pretty widelly available. I prefer otto cats, voraciouse little schoolers. Therey're small enough that they can get individual plant leaves as well as little nooks and crannies; but they can consume a large amount of algea. They also tend to be less harmful to any live plants you may choose to grow. I have three in my 56 gallon with live plants and driftwood and they manage to keep it nearly spotless at all times.
Your options are pretty open, there's a wide variety of little guys you could try.
I would probablly do a school of 6-8 hatchets, maybe 6-8 thread fins, 6-8 rummy nose, 5-7 guppies, 4-5 khuli loaches, 3-5 otto cats, 3 hi fin lyre tail sword tail platies (1 male to two female), and a handful of cherry shrimp.
Best of Luck!