Well, just from a research perspective, you might want to rethink questions 6, 9 and 10. It's hard to see who you are addressing with question 6... seems like you are assuming women in threesomes, ie do they prefer 2 men or 2 women? I'm not sure.
And the last question... maybe you could ask what the overall effect of this has been on the person (not their relationship, because they may not be in one) as it seems kind of loaded as it's written. If you ask people themselves whether they are happy or not with their choices, you may get a more accurate result, although, you are on a polyamory forum...
5. Just a handful
6. I don't have a preference, but perhaps 2 men
8. I have a boyfriend and a girlfriend
9. Absolutely not
10. No sacrifices, everyone is happy