You can just build a megadrum following the schematics on the site and leave out the inputs and associated components you don't think you'll use. Even if for the time being you don't think you'll need them, if you find you like playing drums in the future you'll most probably want to add more pads than just a snare, hi hat, kick and 1 cymbal. The components are cheap, and although you probably won't end up wanting 56 inputs, having at least 10 - 12 won't make much of a difference money-wise from having 5 or 6.
jboogie wrote:do you have recommendations for a cheap drum module + pads? How much should I look at spending at the minimum?
The million dollar question... The more you spend on a commercial kit, the better it will probably be. You can get a kit + module from about 200 euros, but it will most likely be absolute crap. Or you can spend 6000 euros on a high-end kit and it will probably be great. But if you want to keep it cheap, the cheapest option would be to source components, put a megadrum together yourself with the inputs you want, get an atmega off Dmitri and make your own pads; that is, assuming you're into DIY. If not, forget it.
If it ain't broken... fix it until it is.