My two year old, $19, Microsoft mouse has already this with the software it come with. I don't mean to discourage you, but I think you spent more time on the design and execution than developing the software itself.
$19 is a lot of money for a simple thing like that. It's the price of a mouse + a software that customize many things for it (buttons, speed...). However, the niche is interesting. I'll be glad to pay $30 for a software that improves my mouse precision.
Mice come in classes as well. E.g., I use a 69 Euro Apple Magic Trackpad (and disliked plain-old mice ever since). Compared to the cost of a good trackpad it is not that expensive.
I personally don't need the added precision, but if I did, 20 dollars is not a lot for added productivity.
I think you were right on on the price, for a niche market like the one you are going after I think the price is perfect, someone that works every day would see as a minor investment to be more productive or have a more hassle free experience. Of course, you'll learn what the right price is with experience but I think you are off to a great start.
$19 is a lot of money for a simple thing like that. It's the price of a mouse + a software that customize many things for it (buttons, speed...). However, the niche is interesting. I'll be glad to pay $30 for a software that improves my mouse precision.