There are many tools that have upcoming earnings. I used to use optionslam, now I'm using VolatilityHQ because I have a subscription anyway.
The stocks are mostly the candidates we used in the past, so performance page is a good start.
SO Strategies and Allocation provides general guidance about the strategies we use. And yes, using the return matrix to optimize the best entry and exit dates.
And yes, if RV for straddles is okay, strangles should be fine too.
DD have no RV, we just use ONE to see if the chart looks attractive.