I still think the trade hinges on which wonders we plan on building. If we, as a nation, do not want Shakespeare's theatre, it simplifies things a lot. A comment from the Domestic leader is critical at this point in time.
Besides a straight poll of the most favoured option, a poll could include some ranking of importance in each option. Kinda like a priority list, like this:
What should our priorities in trade be:
Metallurgy, Contact with English, Free artistry
Free artistry, Metallurgy, Contact...
etc...
You could then use these results to formulate an idea of the plurality of preference. Do you like this way better? I'm not sure which is better. It could get messy with all the permutations. I don't think you have to get an exact approval for each trade. Public opinion on priorities is sufficient to make your instructions, I think. You could probably even use this thread as a measuring stick enough for your final say.
I didn't say I was for the saltpeter trade, I just mentioned it as a possibility. If, in your judgement, it is a bad idea, then it should not be considered, unless there is much support for it. I'm sorry for trying to do your job though.
Also, if you were to do a poll, may I suggest sooner rather than later? Some people don't have time or access on the weekend for participation.