Thank you knp7765,
I am currently working on the theoretical research side of the technology rules and may need some help with ideas. I will use many of the standard options (Long Range Aircraft, Heavy Bombers etc) but I aim to expand these ideas even more. I will likely create a tech tree with different starting points (Air, Naval, Land, Industrial etc) that sprout outwards and even cross over/link in with each other, with the more advanced techs requiring prerequisite techs. You will still have to use the research tokens which you can accumulate over the turns. More on this soon.
As for the practical side of things, I have made no hard & fast rules stipulating that any given unit type may only be upgraded once per turn. As it stands, players are welcome to invest as much as they want, per turn, into the design of their choice. So if you really wanted those Improved German Tanks on your first turn, then yes, you could indeed spend the 16 IPCs and get them!
Unit Technology Cards coming very soon…