Welcome to the community!

That sounds like a good strategy. The hardest parts out of this plan should be actually unlocking DRG and BLU. I don't think it would matter which one you unlock first.

WAR is a solid first choice, especially for where you plan to eventually go. My question is why are you planning to take THF to 30? I don't think it's a bad idea, I'm just confused why you put it in. I personally used THF as my main sub on DRG until I lvled SAM.

Good luck!