well you will find a zillion uses for it as big as your ideas. you will need patience too and that's because some models needs hours and hours t be done.
build volume i an important factor but not the most for me, the precision is the most important factor and that will define the quality of the models you will get.
try to buy one with convenient build volume so you dont have to split your model into many pieces. and also a good experience in 3d CAD design will be helpful to create custom models.