I think what you are doing is forgetting that there is the playerphase.entity and playerpsi.entity and playertech.entity
what i do, is copy the playerpsi.entity and rename it playerTlani.entity inside the file it still says psi and i LEAVE THAT ALONE.
the ship names you can change in their file names as well, say the Captial_TechBattleShip.entity copied and renamed to Capital_TlaniBattleStar.entity, those will need to be added inside the player file, check out the list of capital ships, the research and all that stuff in the player file. Be careful not to change too much, and if you add things to change the count for each area. It takes time to get used to it.
But the ONLY thing you need to change the name of your race, is to change the outside name of the race on the playerpsi.entity file (as an example. You can use any of the races, just rename the outside and leave the inside name alone) When you load the mod, or if you changed the original files, when you load the game, just click on the race button and it will cycle through all the playerxxxx.entity files in the gameinfo folder. You will see it. Now you have your new cool race name!!!! 
Or if you want the easy way, haha, let me know the name and i will make a mod with their name in it, and leave everything else the same. 
-Teal
p.s Ahhhh... Trade Coalition... yes, those are random names used in the string folder and those entries would have to be removed or renamed would be easier, though since they are randomly assigned you might have the Federation for one of your Klingons, which might be as bad as Trade Coalition,
Best to remove them then, just be careful, if the count for the string folder is off after editing, it will crash the game, so you will have to count not lines, but the StringInfo lines, those are what are being counted, even if the name of discription goes on for three sentences underneath it.
Anyway, give it a try, again, slowly, or have one of us here in the mod forum give you a hand,
then you can have your Klingons and your cake too.
er Federation... 
-Teal