So, to the question, is 3% return per month a realistic goal. Sure, it can be done. Not by everyone, only small percentage of traders is profitable at all. Best ones make more and most do less. So it all comes down to how good is your system and how good of an trader you are. You have atleast an right attitude and don’t try to become millionaire in few months. But have to say, Im bit skeptical on too simple rigid systems, I doubt that the moving average crossover system will make you that 3% per month.
I have personally gotten a lot better results after I abandoned trying to follow different systems, and read a lot about candlestick patterns, resistance levels, chart patterns etc and spend a LOT of time trading demo account. Currently I trade mostly 5 minute charts and spend 4-8 hours a day doing it, and I really have to say that there is nothing that can beat pure experience, after all the work done, reading the charts come “natural”. While I understand that you may not have the time to do the same, I truly believe you could benefit from trading demo account on smaller time scale.