Sirion, Oritolon, Greater Aenilia. GA could use nobles, but to fight rather than region upkeep. Sirion, maybe but only because their war ended and have lost 1/5 nobles in the past few months and even then only a few.
There has definitely been a period where every region in Sirion had more than enough knights, and it was almost difficult to find place for new ones. Such an overcrowding led to amazing military performances, though. Now I wouldn't say there are too few knights in Sirion but certainly it's a whole different story.
