That is a coding change that has to be made by SoE. They keep saying that the game is hardcoded against any more than slots in an inventory container, and that there are similar difficulties in expanding the bank. They get asked this every day, you can do a search on official forums to find the various threads.
Basically, it is something that everybody wants, but it is probably not going to happen
One thing to think of though, is that you can create your own guild on an alt, and use that toons bank and guild bank for storage. You have the shared bank 20 slots to use for transfer between toons.
Bank Space
Linear Mode
