Techtree, unending logarithmic branches
just a thought.. few 4x game has use for science in the end game except a scientific victory.
I usually try to out tech the other civilizations in 4x games. and don't play with victory condition other than domination. ( i like the long games that I use months on), usually in 4x game I mod the tech to take 10x time to be enough stuff to research throughout the game, but this unbalance research to other industry.
What I would like to see is that some branches can be researched indefinitely, for higher and higher cost per level. this way every science
facility does not become obsolete in the end game.