How much of a difference is there? I know about 6", but would that 6" be a really Huge difference, or would it only make a slight one? I'd be putting in 6 cory cats, 12 neon tetras, 6 embers and a betta(assuming the one I just moved into the 29, which is still unscaped, gets along with them) Would that be too much visually, or would it be a decent tank? About 1/3-1/2 is going to have mostly taller stem plants, and the rest is going to be low(I've got it worked out, it'll look nice, trust me

)
The basic design is going to be based off of making Peter and the Wolf into a tank(hey, my mommy always told me that imagination is a good thing

) showing the forest(and open gate

) as if it was through the windows of Peter's grandfather's house. Assuming that he's in a "round" yard, would that sort of curve(although I'm planning it to be a bit straighter instead of trying to mentally draw a perfect circle inside the tank) look okay in a shorter tank too?
Only asking because I'm upping the size of my reef tank soon(ish), and was considering putting it into the 29 gallon so I could have a 3rd fish or so in there without pushing the bio-load too far.