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