I've tried playing with the limited research admin house rule, and one thing I noticed is that it tends to discourage research specialization: I typically had many more research facilities than could be used by my best researchers, so I ended up assigning lots of mediocre researchers to work on lower-priority techs. Since I was playing with two player factions, this meant that both factions ended up with more or less the same technologies, which was somewhat boring. Of course I could've just built fewer research facilities...
I think I ended up changing the house rule to (admin capacity)/3 with like 50% research speed, or something like that, which allowed the two factions to specialize a bit more.
Anyway, I'm still a fan of the new option. It would be nice if it were a bit more customizable so we could really tune the admin capacity/research speed to our liking, but I'll take what I can get.