ilvl 70 gear is very strong, however takes a lot of runs especially time consuming with the recent nerf to speed runs. You get 80 - 100 per run, peices need 375 - 825 each.

ilevel 90 gear is the highest ilevel, and takes myth tokens, currently capping at 300/week. They cost 375-825.

Alternatively you can get crafted ilvl 70 gear which with materia and an absurd amount of gil is arguably better than Darklight (ilevel 70).

Alternatively you can get dropped ilvl 90 gear from Coil of Bahamut which requires a skilled and coordinated group. It is faster and many pieces are more itemized for your class.