Re: x axis homing to left?
PSU = power supply unit
The more current you draw from a power supply, the more heat it generates internally (and usually the more wobbly the power output becomes). Heat tends to reduce the overall life of electronic things somewhat, but this is hard to confirm or predict most of the time. Also, when loaded heavily, the voltage output can be lower than it should be and vary quite a lot (often at frequencies you won't see with a multimeter), and this may not be acceptable to the solidoodle board (if it's not happy, it will let you know with heater errors etc.). A partly-loaded larger supply usually produces much cleaner output than a fully-loaded smaller one.
As excited as I am by printer mods, I'll reiterate: try with the stock supply first, our experience shows nothing's going to die on you!
Smoothieboard via Octoprint on RPi
