Very cool mod. It really screws late game blueprints =P

Have you consider having a mode where instead of research tech the efficiency upgrades come automatically from making the recipe?
The more you do the recipe the better you get at it. With some geometric growth on the cost for each upgrade.
So you get the first one at 1k units, then at 10k, 100k, etc. The growth factor could be a config.

I'm sorry but currently it can't be implemented.

The https://mods.factorio.com/mod/Milestones mod seems to be able to keep track of craft count and trigger events when certain thresholds are reached.

I checked the mod how it works, and as a control method I had come up with, however there is a very small problem, with huge industries you can have 2 problems,
1: the mod takes a long time to figure out that x items have been crafted
2: it can cause lag in the game, because you are talking about checking every single assembler in the game every x tick, and I think you will have noticed that with medium industries you start to feel lag when a new tech is searched, the motivation is just that, checking and modifying assemblers, let alone if it has to be done every x tick