I say let the 3 kitties races stand on their own. If you really want to drop the 3 sided aspect of the server, drop the Gorn, and let the Feds, Klink, Hydrans, and Roms fight the 3 kitty empires. That, I think would fit the storyline after the other 2 servers better than adding another race in with the kitty side.
Just because we have 8 playable empires does not mean you have to split them 4 vs 4. No matter how many empires are on one side or another, it's not going to change the playerbase. I would not be surprised to see a big turnout for the kitties even with only the 3 original empires used in the previous servers.
As for having the Feds and Klinks on the same side, I think it's about time pilots from both those empires take the rare opportunity to fly with your typical enemies. Every other race has done it on past servers, and it's about time the Fed and Klinks do some flying together as well.
Just my thoughts.
AGAVE