“In fact, there are so many ways to be helpful that most companies have no problem coming up with areas to invest their time and energy. Instead, the problem lies in figuring out which areas are highest-leverage.”
But then you conclude that companies should invest in anything that might be helpful and that the real goal is to help in all ways. (“…nothing earns ongoing engagement […] like comprehensively bridging the space between”).
I believe you can iron out this wrinkle by claiming that
1. All gaps should be investigated for high-leverage opportunities
2. There is an emergent property of being comprehensive “a one-stop shop” that you can start to get at and it creates additional increases in engagement. (A 2nd level of bang for bucks.)
Or you can stick with your original claim that increases are linear, but then there is good sense in leaving stones unturned.