How to structure a sales process where the vendor and the affiliates could benefit best?

I would too, but I'd do that separately: I wouldn't expect to build it from my own affiliates' leads.

Not if I wanted good, professional affiliates, anyway: I'd expect, that way, to attract only the ones who haven't thought it through (and call me a skepchick, but those aren't the affiliates I'd really want).

I don't see where it's relevant to what we're discussing, but clearly it's true.

When one is being an affiliate, one acts as an affiliate. When one is being a vendor, one acts as a vendor. The fact that a particular vendor might also be an affiliate, for other products, does not magically entitle him to build his vendor's list out of his own affiliates' leads, does it?

It's answered here, I think, Abdullah: we don't promote products whose vendors are trying to build their lists out of our leads. Why would we, when we don't need to? On ClickBank alone, there are about 15,000 active products from which we can choose. It's "market forces". What you're really saying means, from the affiliate's perspective, that you want us to send our traffic to your sales page and you want a shot - one way or another - at opting our leads in to be on your list, too, and yet you still want us to promote your product rather than that of another vendor who doesn't expect that from us.

Why not follow the example of so many vendors, as discussed in such detail in the thread linked to above, and have two versions of the sales page: one without an opt-in for "more serious affiliates" and another one with it, for affiliates who aren't trying to build their own lists (they may not bring you so many sales, but it's perhaps "something extra", from your perspective, and it's easy enough to do)?