Rewards are iffy, really. Loot doesn't hold a lot of meaning for me, but opening the special Khan Ur thing with a chance at 5-6 special skins and getting a generic yellow every time seems... bleh.
Same with the new skin for Jackal (which I don't need, I get so many jackal skins it's silly already), available from black lion chests. Converted some gold, bought a few keys, and didn't even get a Rare unlock at all, let alone the one I wanted. Certainly doesn't make me want to buy more keys to try again.
The Ash event chain seems glitchy, but most of them are enjoyable.
For 5 silver you can also rent a derby tank and drive around in it all over the zone until it blows up.