Honestly, the Settlers: New Allies is an addictive & fun RTS that will continue to get better with time! Overall, it reminds me of a more economically complex Northgard -- without the survival aspect of Winter & the playstyle overhauls that clans offer (the Settler's faction choices don't completely alter how you play the game like NG clans do).
There are a lot of hidden complexities between managing your engineers, carrier populations, resources/economy & efficiency, army, and, finally, your time. All of these things are crucial to your Settlement's success & all simultaneously demand your attention . If you tunnel vision then everything falls out of balance (e.g. "oops I forgot to build more residences so now I only have 10 guys delivering goods for a city of 200 with 7 buildings actively being constructed & they're nowhere near each other").
-> Graphics & UI are great
-> Music is a lot of cozy, soothing, feel-good acoustic guitar
-> Battles are epic
-> Strikes a good balance between simplicity & complexity that scratches the RTS itch in an accessible way that isn't overly complicated to learn/manage
Minus one star for early technical issues that make the game hard to play online (application crashes, server issues, hit-or-miss server reconnection, etc). With that said, I have hope these issues will be swiftly resolved by Ubisoft & Co. as they are currently affecting everyone.
FWIW -- I've never played any of the other Settlers titles so I have no bias towards this entry.