I just noticed that the research for the artillery delivery is quite cheap in comparison with what is before it. You just finished Artillery(2k packs of 1-3, military and high tech). Then comes the research for Artillery Delivery, which is priced at 200 of science pack 1-3.
I'd suggest at least add high science pack and maybe add production science pack. I don't think military science pack should be added as a requirement, it is not a military tech after all it only 'repurposes' something military. Next to adding some packs I'd say that upping the price would be logical, maybe 1000 packs. That late game most research facilities would not even 'notice' the research being done with 200 packs
Of course that is my opinion. I would be interessed in how others think about it
