In my experience anubias does not "lean". They simply grow with the leaves perpendicular to the incoming light, and once grown leaves stay completely put. If your light is small and in the middle then anubias on the edge might grow a little leaning towards the center.
In the past I grew a tank a lot like yours. Java Fern, Anubias, no ferts, 25% water change/wk under an 18W T8. Growth was extremely slow, but also virtually flawless (0 leaf algae, 0 leaf defects, etc). If you are happy with a slow growth rate (think 1 leaf/mo on the anubias), then this is actually a really good way to go. Also I would drop the temp to 77-78, 79 is pretty much topping it out for black neons, and you don't have anything that really needs warm water.