I haven’t had the opportunity to play Arcs or Earthborn Rangers, but the group I play with loves them.

I usually like very adversarial games, kind of the opposite of what you’re looking for. Anyhow, here’s some current favorites:

Dune - a classic from 1979, it’s super thematic and cuthroat, and established a lot of modern game mechanics. It’s a sci-fi theme, and a good one, but it’s really only playable with 5 or 6 players.

Inis - Celtic tribes clashing with one another about who’s gonna be king. Super interesting card play combined with area control. Mega bonus points to this game for being really good with any player count from 2 to 5, a rare thing!

Imperial and Imperial 2030 - similar to Risk or Diplomacy, but where you the player is not representing any particular country, but rather are the shadowy billionaires who pull the strings behind the scene to affect world affair for profit. Great fun, it’s basically like Diplomacy, but where the goal is to get rich off of the wars of the great powers. This is a 3-6 player game.

The Estates - play as crooked developers trying to build a new housing subdivision. This is one of the most insanely cuthroat games out there, and it’s entirely possible for the game to end with everyone having negative points. A 3-5 player game.

Love Letter - a really simple 15 card mini game where you’re trying to pass a love letter from person to person until it reaches the princess. A 3-4 player game.

1830: Railways & Robber Barons - part of a series of train games where the focus is on stock market speculation. When you’re starting out, you think “oh, this game is about running really good train companies”. Once you get some experience, you realize “oh, this game is actually more about obstructing other people’s train company so you come out relatively ahead”. Once you get a lot of experience, you realize “oh, running good companies is irrelevant, this is all about just being an absolute menace and using underhanded stock manipulation”. Not an easy game series to get into, but a great one for people who want to play competitive spreadsheets against other train nerds. Mainly a 3-6 player game.

I also have been playing a lot of the COIN series of games, which are about historical counter-insurgency warfare. These can have pretty problematic politics if you actually read the playbook (the designers are sometimes chuds), but they’re pretty interesting for storytelling an alt-history. My favorites of these so far is People Power, which is about the fall of the Marcos government in the Philippines in the 80s, and then A Distant Plain, which is about the aftermath of the US invasion of Afghanistan. These are mainly 3 or 4 player games, but they have very good bot players (you follow an action flowchart), so you can play these as 2 player games. These are pretty meaty and difficult to get into, but they’re a blast to play.