There is so much to this that your experience is unavoidable, I’m sure we all get that.
I’ve become so selective after live testing well over 100 systems now (yes I know, a junior), that I do wait for a pullback in equity curve or draw down to commence a new system for live testing with a single contract for up to 3 months. The only exception to this is if I’ve just changed a filter on a proven system because I found something better for my needs. Any more mods than that and it’s a new system and must pass all the usual tests ie. count test, limited data, 1:1, benchmark, incubation, system score and productivity expectations then live test and review.