The bigger the bundle, the better. Schwartz makes one fascinating point. Even if not all the grouped pieces are seen as valuable for all customers. Real-time quotes were the expensive domain of pros only two years ago. Or, at least, in return for super-cheap commissions.
Most folks do.
When you introduce a new product, offer them a discount off the regular price. Do the same for your affiliates. Both deserve it. They'll appreciate that you appreciate them. Quantity discounts are really worth considering, especially if you are shipping hard goods.