I was playing a diplomatic, haggling merchant type character and ended up with a lot of gold. Only being able to go up to 1,000 was very tedious for withdrawls and deposits was very tedious, especially going through the whole dialog tree every time. My suggestions are either of the following:

Have another, higher withdrawl / deposit option (5,000, 10,000)

OR, even better

have a repeating dialog tree that lets you only press one button to keep depositing 1,000 (or whatever amount) before exiting. So a repeating dialog tree that lets you continually select the monetary amounts or exit the tree.