To avoid random, they gives us Tome to exchange gears we needed.
To sustain the progress, they have to add higher ilvl items for people to keep going.

T'is where it's going wrong...

If ilvl remained next future patches, they have nothing to keep players in games.

For future patches with ilvl 210 remained as highest, what could be done?

Add slots for melding, materials that are not stats. (Since they are going to do it anyway)
Special effects, and obtained from Random Dropped of Diadem Extra Hard Mode.
Dropped rate low, and allow FC to group up to farm.
Different NMs drooping different a jobs special effects materials.

No more times exchangeable gears and so on towards end of 3.xx.

Raised only ilvl in your next expansion when you lift up our max level from 60.

P.s. My 10 years old niece was asking : why a level 60 job wearing 210 gears? When you are level 99, are you wearing 1000 gears?