3% premine or 3% taken of every block, there is no real difference. Either way the devs end up with 3% of the total coinsupply ... which is huge!

Just for example look at AtheistCoin (not trying to sell you on that one, merely a good example), those devs put in a lot of time too, it is also Groestlbased and has no premine, no rewards for dev and no IPO, those devs are not trying to fill their own pockets .... also the donations for charity at AtheistCoin are on volunteer basis not a mandatory 10% of every block ... those guys are giving the right example in this land of (hidden) premines, IPOs, percentages for devs and so on... their philosophy is (and I agree with it), if your coin is good and you trust in it as a dev you don't need a premine or a percentage, just mine and trade it yourself

Don't get me wrong .. I think this coin has some very good ideas and could be a success, I really like the built-in miner (although I wonder how you are going to deal with GPU across platforms etc) and Groestl is a really nice algo ... but mandatory 13% of every block is way, way too much. Allow people to donate volunteerly and remove the 3% pocketfilling of the dev and I will mine this for sure.