Expansions increase the game's level cap. For example, one expansion raised the cap from 50 to 60, and a later expansion raised it from 70 to 80. Check the specific expansion listing for the exact cap changes for each release.
Yes. Some expansions add new travel features—most notably flying mounts—and also open up larger new areas to explore. Availability and access rules vary by expansion, so consult the expansion notes or product details for exact mount and travel features.
Expansions commonly add new playable races and major zones. Listings specifically note the Au Ra race and the City‑State of Ishgard, and describe expanded regions such as the Sea of Clouds and floating landmasses.