I do artificially slow down the colony rush by kneecapping the AIs pretty harshly early on. And that's without keeping research planets for myself: I build them and sell them to whichever AI I gave my econ treaty to, so I can get whatever techs they research. Once one AI starts researching tech victory, I kill them off and give the econ and research planets to the next AI on the hit list.
You slippery gypsy Willy! I love it! I'll be giving that a try!
Although remind me to never play a multiplayer game with you hahaha!