Are asteroids always part of the set up process? Does anyone battle in the open vacuum of space? If only one player wants asteroids, but the other doesn't, who "wins"?

They're part of the standard game, but that only really applies to games played in competitive events. You don't have to use them if both of you agree to it.

If only one of you agree to it, you're really at an impasse, same as if you couldn't agree on the number of points or other stuff like that.

I suppose you could try to compromise and only use 3...

If you are playing in a FFG sanctioned (or prize awarded) tournament, you follow the tournament rules and each bring 3 asteroids. Outside of that, anything goes. Nothing saying you can't bring all of them or 1 each. You can eliminate the alley on the sides or the whole board if you wanted. Primarily they are there to improve the tactical challenge of the game, but it is a suggestion, just like the 100 point squads. At your table, you can be as creative as you want. It's better to ask the other person first though...

Personally, I find them quite tiresome. And space is supposed to be full of 'space', not a never ending asteroid field. But the tournament requirements are for asteroids in every game, so that's what you get.

Personally, I find them quite tiresome.

I have mixed opinions on it.

On the one hand, you're right, space should be mostly empty, and playing without having to think about them is liberating. But since they're required for tournaments those of us who play in them use them to avoid developing bad habits.

And space is supposed to be full of 'space', not a never ending asteroid field.

Which was my thought on the subject. But I have been working on my skills at arc dodging, and wondering if the lack of asteroids (we rarely use them) is one of the meta assumptions for successful arc dodges.

without asteroids it would feel more of a jousting game.

e.g.

point click hit and then see what's left after the dust settles. I feel the asteroids are an important part of a match as they help shape the battlefield and make people have to work for their victories. with them some ships are basically doomed to oblivion

And space is supposed to be full of 'space', not a never ending asteroid field.

Which was my thought on the subject. But I have been working on my skills at arc dodging, and wondering if the lack of asteroids (we rarely use them) is one of the meta assumptions for successful arc dodges.

Very few players play without them. Most people are either playing tournament-style dogfights, which always include 6 obstacles, or they're playing some kind of mission or campaign game. Those games vary substantially in how many and what kind of non-ship elements are included, but they rarely go entirely without obstacles.

So no. Successful arc-dodging is not predicated on a lack of obstacles, and in fact the shape obstacles give to the field (and the corresponding reluctance of many ships to get too close) are an important part of tournament-style arc-dodging.

One interesting way that I found you could play in a casual game with asteroids is if an asteroid is within range of a bomb token when the bomb detonates, then place a hit token on that asteroid and treat the asteroid as a debris field. Came up with this idea from the sequence in Attack of the Clones where Obi-Wan was trying to evade Jango Fett in the asteroid field above Geonosis and Jango releases a seismic charge turning a nearby asteroid into a field of small rocks. It definitely adds some versatility to the game and keeps everyone on their toes when the board is changing. We have even thought of the idea of if one of our asteroid debris fields gets hit a second time, then the small particles that make up the debris field will just vaporize, then remove the asteroid token and turn that area into open space. Haven't implemented that into a game yet but something we have considered. Now mind you this is all for casual games and not for tournament play. If you are looking to hone your skills for tournament play then you should probably follow tournament rules during most of your games.

Wouldn't an empty space get boring way faster than asteroids? No obstructed attacks, no having to move around asteroids, no near misses and unexpected clippings, no accidental missed opportunities to fire ... sounds a lot more boring to me.

You can also park an epic ship. I think they are supposed to count for 3 asteroids.

You can try playing with the debris clouds instead, they work slightly differently.

Low defense ships can use obstacles as cover to get some extra green dice, making a focus token pretty useful.