I've spent a lot of time on a automated trading side project of mine but haven't found the strategy yet.
In retrospect time has been spent in completely the wrong areas ( setup a solid backrest platform first, duh )
Warning: it is a lot of fun, thrilling, but hard to make money. My winning algos took a while to research, longer to automate, and often lost alpha quickly.
Backtesting is great for validating ideas initially. Especially, to see if it holds up through abnormal markets like '08, or the volpocalypse, or the recent crash. Watch out for curve fitting, though.
Do you apply ml techniques? I don't suppose you could point a little in a good direction to follow
Something like using NLP on SEC filings the second they come out to catch an initial jump in the underlying would be cool to try out.