Not sure if the developer nerfed the physics or if the people posting videos on youtube hacked the game, but after 2 hours of trying for the hard badge I've concluded that one way or the other, I'm not playing the same game they were. + if you think the hard badge is impossible.
Lv.7 The Sun Emperor is a great way to mill coins--just stand off to the side and summon junk until the timer runs out. It's also a good way to get extra hats. As for what to do with all the coins, maxing out the "Powers" ability (bottom row) seems to be the most helpful early on. Lastly, when it says the Ankh power is usable ONCE, they mean just that: single use and then you have to buy it again, so don't invest in that until you really need it!