For 4 players- Round robin is definitely the way to go. You could finish with a 2v2 team game. I think team games are really fun provided you play on a standard 1v1 size map. This gets everyone mixing it up. The first few times I played teams I thought the map needed to be larger to accommodate, but it just ends up largely being 2 different matches on either side of the board.
Instead of a tournament, you could do a special type of scenario game, such as what
Kolakoski has posted
here. Have everybody come up with 2 armies and play 2 games, that way you get plenty of use out of the set-up and it's enough to fill your game night.
For 3 players- I prefer a round robin here as well, where one player sits out each game. I've done this and then finished the 'event' with a 3 player game of some sort, such as kill the person to your left or a heat of battle free for all.
For 2 players- While just playing a few random games with 2 people is fun, I find it a lot more engaging if you can set up some sort of structured event that goes several games. Here's a couple of formats I've used that have worked well.
1. Ideally you'd have 3 maps set-up. Each player builds 3 armies of however many points you're using, I prefer the standard range of 400-600.
The event is divided into two halves. You play each map 1 time in each half, so each map gets used 2 times and you play a total of 6 games. Before each game you randomly select one of your 3 armies (assign them numbers and roll, or draw them out of a bag, or whatever you come up with). Once you play an army it's out for the rest of that half of the event, so each army will get played exactly twice, same as the maps. For the second half of the event, once each player has used each of their armies once and each map has been played on once, you reverse the whip, swapping army pools with your opponent and play 3 more games for the second half in the same way.
2. This one uses the
pod draft format. The
pod draft is where you have a pool of 6 small armies of around 300 pts. Before the game one player drafts a pod, then the other drafts 2 pods, then the first player drafts their 2nd, so that each player has 2 pods. This has been used in some of the online events, where each player brings 3 pods and can then draft from their or their opponents pod pool.
So for a 2 player tournament using this, each player comes up with X amount of pods. When we played we did 10, so a total of 20 pods, with each pod assigned a number 1-20. Before each game we rolled the D20 until we had 6 different armies to form our pod pool for that game. We alternated who got to choose who drafts first. We played this over several weeks playing 8 total games (so 32 pods were used over those 8 games). I think we ended up using 16 of the 20 pods and several of them got used twice, with one or two being selected 3 times.