Quite the clean-up!
I'd say you should only keep as many tops as you think your roots can support. I doubt you would lose too much harvest weight going from 35-40 to 25-30, as the plant will send all the resources not going to what's been chopped to the ones remaining. But rather than taking tops, I would have removed all the larf from the bottom 2/3 or so of the plant.
This is why I don't take off fans when I do a post-stretch thinning, just flowers. If the plant is growing back vegetation in flower, doesn't that seem like that would be taking energy away from building buds? I don't want my plant first having to regenerate new leaves to absorb the light it needs to power the flowers.