I have been toying with various ideas of openers (having taken ideas from pro cyclists and triathletes and ideas from sports science) to try and find something that suits me. Things to consider are the timing, duration, and intensity of the event etc
So what do people do for say a 10m or 25m TT, or a crit or a longer road race.
My old coach always had me doing 3x90s full gas with at least 10 min between. I hated them. If I felt good I races like crap. If I felt terrible in openers race day would be good.
After a few years I noticed a pattern in my workouts and that one style was easy, always started rough but finished feeling strong, and hit a lot of hr zones.
I adopted that workout for openers and have like it going forward.
Go look at what types of workouts leave you ready for more, then step them down just a notch and give it a go