In fact, I aim for 0.5% per week or 1% for two weeks, that’s why I often go for underlyings with higher IV (TSLA, AMD, NVDA). Also, I don’t hesitate to buy back contracts to reduce risk and increase the return if possible.
I’m aware that I’ve been pretty lucky during the first 6 months of this year with only two assignments and a well-greased wheel. 
I made USD 6,000 (~12%) in six months and just transferred USD 5,000 back to my main ETF portfolio to take out some risk.
Happy trading! 