Only you know your group, as to how they will accept this idea ... or not. With your hesitations already, I would wonder if you know what the outcome would be, before you suggest it to your friends?
ITA ... the signature quilt idea would be great. Or perhaps if each of your friends are sewers, they could each do a block, for a sampler quilt and then you could assemble it before the get together.
Someone a while back, did a quilt for their boss when he retired .... each staff member went and bought a FQ that had some meaning re the boss. Yes, the quilt was somewhat of a jumble ... but in reality it was an Adult I Spy ... and filled with endless memories and meanings for both those who gave it, and the chap who received it.