Yeah, threshold intervals would be appropriate now. Longer SST rides would be good too -- not TT hard, but hard enough that you have to concentrate to keep it up or you'll ease up. For you, maybe 160-165 bpm for 45-90 minutes?

I wonder if you're doing the 1m intervals hard enough. If you can sometimes do eight, and they feel like they're of high quality, you might not be hitting it hard enough. These should hurt so bad that you're partially trying to talk yourself out of finishing the workout. Bleeding from the eyes is a sign of a good 1m interval workout.