I tend to keep it simple.
30/30s x 10-12, 10 minutes rest x 2 or 3. Aim for a power hard enough that you can keep the “on” intervals pretty similar.
5x5 with 5 minutes rest. 120% FTP is what I aim for.
Then some maximal 60s efforts with long rest periods of basically no pedalling in between. Aim for 5 to start with, try to get to 7 or 8. With these though you need to be careful, very easy to pull something so maybe sprinkle these efforts in earlier at a lower power or shorter duration. I don’t do gym work but I’d highly recommend it as I’m sure it’d really help.
Just mix these sessions up, the 30/30 I would do on the trainer, the rest outdoors where possible. Ideally on a hill. As with most stuff try to factor in some progression, so maybe start the 5x5 at 110%, then try to up the ante.
2 sessions of the above per week is enough, then just go easy on the other days…
No expert, but you’ll find quite a few people do something similar to this. Recover as best you can, try to do these hard efforts earlier in the day or afternoon if you can.