I really enjoy Production Line. But for Research and also Sales there are some Features Missing in my eyes.
I don`t who remembers Car Tycoon from 2001, I really enjoyed this game, with severals decades of gameplay. From 1950 to 2000 with all new Technologies, car designs, …
Main point in this game was to decide which type of car,which engines, …, to reserach an build. Also you have to buy/build retailers and factories. This gameplay in combination with Production Line would be awesome!
Here is a Youtube link for all people which don`t know Car Tycoon.