I think the research rate for Global is fine if you are doing Open Mode and go on an invasion-spree to add cities/population so that your research goes faster as time goes on. It certainly drags early on, even for the big powers. Research for the middle-powers is tricky. Research for the tiny countries is basically hopeless any way you look at it, unless they survive long enough to add their pittance to their allies in Historical/Random. I found that countries were adding the middle-level units in the early 40s, which seemed fine. No one should be building the Bomb early anyway, right? At least not without sacrificing basically everything else (such as a strong army/navy/airforce).
It would be nice if the 'empty' techs actually did something other than just acting as a stepping stone to the next tech. Doesn't have to be much, but 'something'. Free unit? Free promotions for X units (or a free general)? Free building somewhere? Add XX research points, coins, production, whatever. Something small, so that it doesn't unbalance things (unless someone wants to go through and add bigger things and rebalance it of course). Just, you know, 'something'. Maybe a free great person would be fun, flexible, maybe-easy-to-implement, and not too unbalancing? Or just add XX GP points in the city whose research finishes the tech.
