I think it's finally time to write a review for Expeditions... I have over 600 hrs in Snowrunner, steadily progressing through the newer DLCs, and now 15 hrs into Expeditions, I have finished the first tutorial area, and I've made enough progress in the other 4 regions to form my opinion.
TLDR: It's alright.
Let's start with the elephant in the room: the mission structure. This game is structured completely differently from Snowrunner. Each mission you do is a standalone session where, once completed, you are sent back to the menus to pick a new mission, a max of 4 trucks, and sometimes a different "perk" in the specialists. Because of this, Expeditions simply feels like an arcade game: you pick it up for 15 minutes, complete a mission, and stop playing. While you can stick around after a mission to pick up tasks that are nearby, you still eventually have to return to a menu and have all your trucks removed from the map.
IMO, the solution to this is simple: remove the 4 truck restriction and let Expeditions be started from the map screen. If a different specialist is needed, *that* is when it makes sense to force the player back to the headquarters, either by driving, or by recovery. Letting players keep trucks staged between missions in preparation for the next task is one of the best parts of Snowrunner.
Expeditions does, however, have some great maps. While the diversity is abysmal (4 desert regions out of 5 total), the map quality is quite high, and rock crawling and the lack of roads is a great departure from Snowrunner. Driving inside caves in the most recent DLC, while quite unrealistic, is REALLY cool and something we definitely haven't seen in Snowrunner. Having multiple headquarters on each map is also a nice addition, being both a way to reduce the distance traveled for certain missions and a way to make it feel like there are more maps since you will be seeing each headquarters A LOT with the terrible mission structure.
I'll lump the rest of my thoughts into one section, as most of them will simply be overcome with time. Certain decisions with this game seem asinine: The controls feel like there was a meeting specifically titled "how do we set the controls to mess with Snowrunner veterans the most", and the UI is needlessly convoluted. Sure there are some diamonds in the rough here (like not having to close the menu after using tools like the which), but having so many different UI menus for all the different tools and mechanics at your disposal is quite confusing, even after a decent chunk of time in game. The inventory system is another needlessly convoluted thing that still makes little sense after 15 hrs: there are 3 different types of inventory, and the most visually obvious ones can only be filled with fuel and parts using one of the most hidden menus I've ever found. Updates seem to be significantly slower than Snowrunner, and while we are finally getting things like Snowrunner controls and a compass on the map screen; these are things that so obviously should have been in the game at launch, but we are getting them at the cost of a 4 month DLC delay.
In conclusion: If you are looking for a sequel to Snowrunner or Mudrunner, this is FAR from that. But if you do your research and know what you are getting into, there's plenty more content to be enjoyed, it's just stuck behind really kludgy UI and game design that will limit your want to play into shorter sessions.