While I agree with your sentiment and find your reasoning to be sound the last part caught my eye. Homogenization should not be a goal and it is a problem in 5e and generally there should be clear cut reasons as to why one source is superior to another in certain regards. While I don't think perfect balance is ideal I would prefer that the best choices are tied to classes and character while consumables can offer you alternatives not otherwise available to your selected party or have niche benefits.
I dont really feel that classes are not distinct enough. They all have their strengths and weaknesses. But they are balanced in a way which is not over all favoring one playstyle or class over all the others. Perfect balance is pretty much not possible, but good balance with some specialties and fun party interactions is a great thing. What are the problems you see with 5e? I only have 5e and some Pathfinder experience.
