Something unique that's not tradable.
Some possible ideas for what i would like to see as a plat tier reward in the future.

2 skill points.
100 inventory slots.
30 platinum / 1 free massive ren'gol crate platinum-less open.
Limited edition event gear (not vanity) with "decent" stats.

There should be another extra reward benchmark that returns half the pots you've used and 1/3 of ankhs from the start of the event. Just a bit of compensation for working so hard i think. Eg. If plat tier is 5k points. After a player hits 15k points they would receive the compensation.

Thoughts?