I think you should add a few higher levels (>200), with some virtual rewards. For people that want to support and have some extra cash on the side, but don't need 5 keyboards. Remember that kickstarter steals quite a lot of money in taxes (40k out of those 55 will probably reach you, if 70 euro out of each 100 is enough then disregard that)
edot: especially when the time will start running out and there will be a bit left missing (typos fixed)