Having one end of the tank dim is not a big issue. I can use a CFL on that end to get some light, and there are no plants in that area. The goal is actually to get the plants thick enough to give my kilifish some cover to spawn/have fry survive. I do have a wooden canopy, so raising the light is not an option.
I would like to get the lighting up for as cheap as possible. This tank has another year to run, so no use in spending a lot on 72" lighting. I would never go this large again. Cost too much for hardscape, substrate, etc.