There are SO many options out there, but if you are looking to do an egg-scatterer of sorts then you might want to have a second tank so that you can remove the parents while the eggs hatch. Then that enables you to do all sorts of tetras, barbs, rainbowfish, etc...
...but if you want something that turns your planted tank into a low-maintenance baby factory, then I recommend kribensis cichlids. They're colorful, do well in planted tanks, and they can even accept tankmates during breeding (depending on the size of tank and the species of tankmate).
They're SO easy. The pair in my planted 55g has laid eggs scores of times; and if I had removed the fry or other fish in the tank, I would have ended up with several thousand babies over the past couple of years as opposed to about 100. I actually had a lesbian pair for a while as well, when the original matriarch and patriarch split up and each paired with one of their daughters; unfortunately they broke up after several months together. Anyway, my kribs have had the following tankmates over the years:
Bosemani rainbowfish
Celebes rainbowfish
Angelfish
Red-tailed shark
Pearl gouramis
Upside-down catfish
Plecos
African killifish
BGK
Roseline sharks
Neon tetras
Female bettas