Well, I wouldn't be interested in paying for npc / monster creation tools, unless they offered A LOT more than what is currently available in your free tools.
In fact, while I tried using them to create the statblocks for my next 3E adventure, I quickly switched back to creating them manually because there's simply too many things that (currently) aren't supported (or at least I couldn't figure out how to do it).
Some crucial things:
- all relevant details to run the monster/npc should be in the stat block
- support for buffed/unbuffed versions
But the biggest problem is frankly that I want to use and have access to all of the non-SRD material I own.
As an outlook: I expect my 3E campaign to come to an end within the year. In September my group will give 4E a try. I assume (and hope) at least some of them will be interested in continuing to play 4E which would end my interest in 3E tools.
While I'm considering to pick up the Pathfinder rpg, I don't expect to actually use it. It's just to sate my curiosity.
I am planning on allowing users to populate their personal monster database which will be then available in their monster selections. You can then create and level up your own designs. (or create similar ones to those in the other books).
Buffed/Unbuffed verions are a good idea (I could add a spells cast/Potions taken flag), I'll look into this.