Hi there~ Welcome to FFXIV!

1) Crafting, gathering, managing my FC, putting together or grinding for new glamour parts/looks. I also run high end content to practice my tanking skills or refresh my memory on my DPS (RIP Monk)
2) Answered above, but most content is good enough you can go through it once a week for a few weeks, or once a day without being bored.
3) As above, innovations are tested out every other patch. They can range from new areas (Diadem), to concepts (Randomized dungeons or loot), to new boss fight mechanics (rare, but it happens).
4) I play for quite a few hours every day after work and such, but I probably play too much.
5) Already answered above.

Bonus question : Some say it's glamour.

Take care!