Honestly, I think the teleport costs should be able to breach beyond 999 gil.
In the grand scheme of things, 999 gil really is not that much. i have a steady total of approximately 3~3.5 million gil, and that's considered as "little" by a significant part of the playerbase! And just look at the amount of gil people who actually bother to use their crafting and gathering classes are making. Hell, I don't use gathering and crafting professions at all, I get my gil exclusively from drops, roulettes and putting random junk I find on the marketplace, and still these prices of 999 gil per teleport are not making me any poorer.
Not to mention, it's a good way to at least try and regulate inflation a little bit. There isn't really a lot of things you can spend gil on in this game, except for raid consumables and maybe very rarely a pet or a mount. But that's about it. You can get anything else practically for free, through grinding, or through currencies that are not gil.
