I have played about 10 games under Beta 4...typically large map with 4 or 5 AI's. In every game, I quickly generate MUCH more research than all the Ai's...in the most recent game, by turn 250 when I "retire" (to check progress) I am in the middle of the pack in Income, Mana, and Might, with slightly higher population - and with a Research score of 200 versus a Research score of less than 20 for each of the AI players. Looking at the Research Graph, I start to gain Research at a much faster rate than the AI's right from turn 1, and the gap steadily accelerates. And as I said, this occurs in every game.
I am using a custom soveirgn and faction, but neither has any traits that provide or multiply research in an yway.