In the advanced options:

1. in the "Starting Position" menu: additional option "Random Opening" (to be determined when game starts);
2. in the "I Play As" menu: additional options "Black if I'm higher rated, White otherwise" and "Black if I'm higher rated, White if I'm lower rated, Random if equal";
3. additional checkbox "Only open to Friends" (or, alternatively, seeker can enter the reserved word "Friends" in the "Opponent" field).

Thanks for your thoughts.

Nice suggestion! I would like the 1st suggestion the most, it would get players used to different openings. Only thing is that (it probably won't) but sometimes it could choose bad openings like -

Sicilian Defense: King David's Opening (B20)

The advanced options really need a checkbox for "Exclude members I'm already playing" - or a field where you can type a member's name to block a specific person from accepting this particular challenge. The reason for this is I'm playing a guy at the moment who has put out about 10 seeks (and who incidentally has over 140 games going!). Whenever I try to start a new game I'm automatically paired with him ... but I don't want to play 2 games at once with the same person. He's monopolizing the open-seeks board, and while I don't have a problem with him wanting to play a ridiculous amount of games I would like to be able to avoid him without blocking him completely.

Maybe this could be implemented by allowing nicknames prepended by a minus sign in the "Opponent" field, similarly to how you exclude keywords from a Google search.

For the time being, I think you can get the same result by temporarily adding that member to your block list (My Home -> Account -> Privacy) until your seek is accepted.