My dwarf green japanese maple is 9 ft tall and only has growth on top from where i've pruned off the top foot each year to encourage fullness below. It is now bare the bottom 2/3rds. It is planted in an protected "L" part of the house. Too much shade but compliments the red weeping one on other side of house. Also-why doesn't my avocado pit show growth? For 3 months its been half submerged
Most new growth will appear within a foot or so below where the pruning cut is made. If you want more growth lower on the tree, you may need to cut it back farther. The low light conditions compound the problem. If the light levels were greater, the tree would be more likely to sprout additional branches farther down the stem.
As long as the avocado pit is firm (not rotted), there's hope that it will still sprout. They don't have any particular dormancy-breaking requirements, so it's just a matter of time for them to sprout. Also, keep in mind that 100% germination is not guaranteed. Occasionally some will not sprout.