I'm sure I'm going to get flamed for this post but here goes nothing. The way it is at the moment, the terrible mob density, mob respawn time, poor loot drops, and movement speed debuff don't make me want to even spend my 40 minutes in the desert each day. In BDO, at least the packs of mobs in the desert are at least close enough to effectively move between packs rather than "ride on camel for 30 seconds, hop off camel, kill 8-10 mobs, hop back on camel, rinse and repeat". Even the animation getting on and off the camel is clunky and annoyingly slow. The runes are an interesting feature, but since they apply to your family, you end up getting useless runes over and over and the low fusion success rate means that you're always burning them. It just ends up being a frustrating and pointless experience. 

That said, I've been trying to level up my excavation skill level and hope for better loot in the future. Even that is a slow, boring process just like hunting mobs. The temple payoffs are great, but I've completed the ones in my CP range. That's pretty much the only redeeming quality I've found after the last few days I've spent there. 

Anyway, I'd like to hear some advice for what I should be doing in the desert because I really don't get it. For now, I think I'll stick with Hadum and build up my time until I figure something out. 

the main reason to farm in the desert is for the elephant. Good luck tho cuz it has a pretty low drop rate on the quest item.
Edena coins are also quite needed for Black rock temples that spawns after Laytenn has died. Later we will get a world boss that spawns only in the desert.
Another good reason to be in the desert is farming for runes.
I get farming in the Great desert doesnt feel as nice as farming hadum or regular Elion maps. The grinding pathern is more like BDO where you have to loop around areas and requires you to play more manually than auto.

As far as KR content they havent really added anything impactful so i feel like the desert is something to do over time.
Personally i stack my water till i have 2 hours and hunt for excavation ( Currently Top 5 for NA Global). The great desert isn't meant to become a really big important first hand feature like PoG every day. Just go in the desert for half an hour and keep the 10 minutes if a laytenn spawns/black rock temple.