How to analyse and prove to business stakeholders that a website redesign (b2b hardware) is better than a previous one?

I'm a lead UX designer at a small company and have been working on a website redesign for our product (we sell hardware in a niche b2b business). The website is obviously much better than the previous one but i would like to take the approach of being data driven to prove that what we have done is better (qualitative and quantitatively). How do I do that? I've done in depth user testing on the previous website and gathered information on the problems we had, but I had LOTS of things from different users, we are not doing A/B but evaluating multiple things at the same time (new visual language, new colors,, new layout, better use of design principles, better content, etc) We only have one conversion point (request quote), I know that we will probably boost the conversion on that point, but I would like to prove other things beyond that conversion. I'm undecided between going to a simple "funnel" approach such as understanding of the product (biggest challenged we had) , interest and intent to send a quote. Another approach would be analyzing in details each point (emotional design, type of content, language of content, colors, layout, understanding of content, how likely the person would make a quote) and show both the old and the new one to the same people.