I've seen the following suggested on meta.SO for similar situations (I can't find the link ATM, but it should be one of the most-voted questions).
If you ask a question and there are more than one useful answers (i.e. both of them contributed to your solution, or you found them to solve the problem independently), you could ask one of the contributors to combine the answers into a new CW-ed answer, which you could mark as accepted. Better yet, write such an answer myself (I was in a similar situation a few days ago, see this question).
The community wiki bit is to avoid conflicts who should get the bonus rep -- by not giving it to anyone, but still recognizing their contribution. The answers of individual contributors would be voted up anyway by the others (and yourself!).
I think this is a reasonable compromise, and in fact serves a long-term goal of having good and up-to-date answers to the questions, as the CW threshold is quite low and the answer can be improved and enhanced in the future.