Personally, I don't think there is much interest in this as of yet because of the basics of the program. This is not a bug report or a bitchfest, but some honest critiques.
1. ST4 Editor in it's VST form crashes a lot, even the new 4.01 version. It's reminiscent of the 1st incarnation of ST4 which was filled with fixes that need to be made, about 9 versions to be approximate. If most users can't open it, what is the use of putting in a user request based on past experiences? People need a sample editor to work or they just leave it by the wayside.
2. Resizing the GUI is a pain. f you own a larger newer screen it's fine, but if you work with smaller older screens, it will take up the entire screen with no ability to shrink it down.
3. No drag and drop really makes this no fun. We're in a day of age where most samplers have drag and drop ability as well as sample editors. Having specific folders for samples to be imported from is an archaic way of thinking.
4. Maybe the idea of making this program a VST is maybe most of the problem. If this was just a standalone app, I could understand the limitations. Possibly working from just on the standalone and getting that better may be more advantageous than working on VSTs. Some ppl may disagree with this, but it's just my personal opinion.