It's time to reevaluate the idea of adding a PLEX/Chronoscroll-like system to FFXIV

[Magis]

Here are a handful of expensive items you could spend gil to obtain:
1. HQ Artisan Gear for crafting (best gear in game for serious crafters)
2. HQ Foragers Gear for gathering (best gear in game for serious gatherers)
3. Crafting/gathering materia for the above gear (ranges from 20-350k each on my server)
4. i110 accessories for coil (used to get dual main stats for advantage in survivability)
5. DoW/DoM materia for Zodiac/accessories (ex. 11+ savage crit 4 @ 400k each and 8+ savage det 4 @ 400k+ each)
*6. Minions (some ranging from 1.5-4 mil each)
*7. Vanity Weapons/Gear
*doesn't help you achieve anything

Not limited to that either:

Buying coil runs for the best gear
Buying out players to give you a pony