UX testing for multiple product mixes

I am in charge of trying a change of product mix that leads what was 5 individual products and converts them into a single product. which can be increased to approximate the previous set of 5 products.

I am already doing quantitative research through surveys on the supply of new and existing products. My validation solution is to create a prototype of the new offer of unique products and perform qualitative tests, in person, moderated with the specific demographics of the clients.

But nevertheless, I wonder if there are other methods to validate the new mix of products that one might recommend out of this.

Any ideas?