I appreciate your patience (?) while we worked to get a response on this issue for everyone!

Are there plans to adjust the purchasable items offered by Grand Companies (for example, PUG weapons are in Gridania, but their guild is in Ul'dah)? I am unsure where items will ultimately end up, so I am afraid to join a Grand Company... I also feel like I have to join a specific company just because of their rewards. AHHHHH HELP!
A lot of people were worried about this, so Triary spoke with Yoshida regarding this issue.

We plan to continuously make adjustments as needed based on your feedback on purchasable items within the GC. Therefore, please don't worry about what city-state has what guild or which items can or cannot be traded, and simply join the Grand Company which appeals to you the most after you hear their speeches in 1.19!

Also here's a good place to address the ability to earn more seals...
Can we obtain company seals through Grand Company leves?
Yep, players will be able to obtain company seals in Grand Company leves that will be implemented in 1.19.