I'd stick to just producing your boost.
Alright I'll concede the point, after spending the morning doing the math (it's all in the wiki now) I determined that in my city, to make non-boost T4 in 7 factories vs boost in 1, it would take
324 AW levels to make it worth considering throwing the seeds in the trash vs the space. Needless to say I'm about 300 short. LOL
As it stands I will in fact be waiting for seeds more than anything else with 1 boost T4 running 24/7... and occasionally making non-boost T1 in it while I wait whether I like it or not anytime I have to use seeds for anything other than running T4. (I'll be making almost exactly enough seeds just to produce T4 in one factory, a little more after Main upgrades)
Edit: and assuming that holds true for the next two chapters it would end up being about 1,000 AW levels to consider it... I don't even think pushers can do that, although it is hypothetically possible. It would only take having and maxing every AW... which might waste a bit more space than 3 off-boost factories.
Note: I suppose one could also just complete 1,000 more provinces (around 1,400 total) to achieve the same thing.
Note 2: There is a line though.