I work at a B2B software company (~1500 R&D, and few thousands of people doing sales, support etc). We have one main product (accounts for the majority of sales) - a hardware appliance with two bundles of licenses - basic and premium. When the product is sold it comes with the premiumm for some time and then it depends on the customer decision whether to renew the premium bundle, pay for the basic one, or somewhere in between (pay for some of the premium features). The problem arises when I want to decide/suggest features to add to the product. I'm being asked how will it affect the sales of the product - and this question is terribly difficult.. sure I can measure the usage of the feature I'd like to add - but it might not affect the bottom line $$$ at all. I can also find examples of features that nobody uses but did improve sales because of their effect on the positioning of the product.
How do you measure effect of a feature which is part of a much larger product? How can I measure if it was significant in the customer decision to buy / renew? any examples?
Thanks!