It's pretty much free reign with your own folks. Don't see any particular reason you wouldn't be able to have two individuals working with others.

I'd probably be free to poke, if you liked…?

If you wanted to write two pairs, you could. If you wanted to write some missions with another person, some solo, you could :) I started off by writing two solo missions, gained a writing partner for my next three, lost the writing partner, wrote another couple of solo missions (one of which I wrote solo but borrowed (with permission) another Boarder's agent as a partner for my primary agent), gained a new writing partner ... and between us now Pads and I write nine agents, one of whom was in fact invented by July, and do/have done/are doing a fair number of co-cowrites with other Boarders such as July, Sedri, Lee, Laburnum ...

Basically the whole name of the game is to a) have fun and b) mock badfic. If you end up creating a veritable army of characters to do so and rope in as many willing participants as you feel the need to to help you cowrite, that's okay, as long as it's fun and it's funny :)

I started out with two Agents and planned two more. I then rescued three in my first two missions, and spontaneously created about fifteen more over the past four or five months, whom I still need to write missions/publish interludes for - both solo and paired up.

Not to mention that I've got at least one planned co-write with two other people, and probably more if the negotiations dont fall through.

...I was going somewhere with this, I swear... Oh, yeah. Basically, partner up your Agents as you please, co-write as you please, etc. There are no rules about how Agents work, and there are occasional teams of PPC writers - for example, as others have said, Jay and Acacia themselves, and Trojie and Pads. Others have teamed up on occasion, too - I recall Rilwen and Lycaenion doing a piece a while back, and I seem to end up co-writing a lot of interludes for my gang with Kgarrett.

Okay, rambly rambling ending now.

You could always create a few more agents yourself.

I started out with one agent, and I have four now. I still like my first agent couple the best. They have excellent chemisty. Or it could just be that the fandoms I've put the other agents in are just not that exciting to write missions about.

You don't need to have two agents- just one is fine if you want to write a solo agent, and some people do write in pairs; the Grand Example here being Jay and Acacia, and a more recent example being Pads and Trojie.

You can find someone else to cowrite missions with if you like, or just do solo.