I have wondered about this . .
Making a 7 replacement, for instance, that has the same level of refinement of the 14 would mean fixing all the intimate details missing in the current design. They can not ignore all the lessons learned by the design and manufacturing team. The business model of just answering the same builder questions over and over has to be weighed agains using that human resource to do new developments. Vans has a lot of growing pains still to go through and must know what the company wants to be when it "grows up". Without sustainable business goals, baby steps by the team in that direction will not be efficient. They are not the little company in with the huge opportunity anymore, they are the big dog with a huge share of the market.
That is going to be a real problem for Vans, growing into a sustainable, competitive product line. The older kits are lower cost, and appeal to a large market, but are deficient in the level of refinement of the later models. A company has to plan for making it's own products obsolete. If not, someone else will. Efficient manufacturing by Vans has shown other companies how to do it. Typically, the best approach to avoid a clean sheet development of a like (replacement) product is continuous improvement, something Vans does not adhere to. They must evolve at some point, and protect that core market of volume. They have come from a small operation and are emerging into an organization with engineering, validation, analysis and a product needing less human (factory) support to build. A market analysis and strategic planning function will be needed. The market for price and performance and size does not seem to have changed a lot in the years, but the product line and emphasis has moved to more expensive and larger airplanes. They will have to protect their core market, and at some point evolve to recapture the volume revenue available in the market sweet spot, or plateau. The next decade will tell.
Just what is the market for a 3, or 4, or 7, or 8 that substitutes more refined instructions for builder skill and appeals more to a 1st time (younger) builders? How does build time to flight affect the market size? Does EAA help quantify this market or just make AirVenture attendance larger? It would seem that people with more money will have less time and that would expand the product sales. The market for built RV's will meet some of those needs. There seem to be a lot more questions for Vans to deal with than just making better instructions for an older (less complete) design. Many possible avenues.