For me, there is alot of things to enjoy throughout the entire game. Not in any particular order below.
1) The early game survival struggle. (Water/food/shelter)
2) Quest / POI Progression
3) Vehicle Progression
4) Horde Night / Base defense Progression (weapons, ammo, traps, etc.)
5) Crafting Progression
Not saying that any of these are in their final form but do enjoy them in their current form. For example, I would love to see crafting gain more benefits, especially once game / lootstage gets higher.