I understand your want to not invest in a tribe you don't want, because truth be told if Brudvir weren't part of the launch I would be in the exact same boat you're in. The problem is there would be many issues with it, namely just because we can't play them, doesn't mean they're not advancing.
To phrase something Orashna said, in a different way, you think that the Mydarri will be at the same point as the other eight tribe were at in expo, which simply won't be the case, or I should say I would expect not to be the case.
It might be the case that the generated infrastructure isn't ideal, or upto player standards, but I would hope that isn't the case since the Devs are going to go over every continent after it's generated and polish it so it doesn't feel so generated.
Lastly, you have to remember that, while sbs wants to balance the important things, somethings make for a better story when left a little unbalanced.
That being said, I would be curious to get Serpentius or one of the Devs opinion on this, because you are perfectly in the right for not wanting to be forced to spend your money on something you don't want to play for the long haul.
Edit: You can be Lesbian and still use child contracts.