I feel like the two can be blended more than that; it just might take more means of entry or acquisition.
A suggestion that was tossed around during 1.x was to anything that could be said to apply to one or more crafts should give experience accordingly, including the final stage of making boots out of intermediate products from leatherworker, alchemist, armorer, etc, and should boost crafter leveling in a way that made it easier to catch up to keep up with one's battle classes. This included the sub-suggestion that either there should actually be more stages in crafting, with additional depth, wherein one goes from high-top moccasins, so to speak, to boots, to armored boots, as to distribute accordant experience across all three crafter that would logically be involved in making a pair of jackboots, but giving further convenience in place of the extra time required to level all the involved crafts (e.g. no need to swap between classes to craft their products, at most swapping to the optimal (prior to all gear having "required" level) gear for each instead such that there's no need to swap when your crafts are roughly the same level). Similarly, non-crafter tasks such using your own hand-made weapons, modifying or augmenting weapon drops, repairing gear, and so forth should all additionally grant related crafter exp.
Another suggestion I saw back then to roughly the same effect was similar to what WoW started doing in Legion, making it easier to skip crafting "material tiers" or focus on specific ones, thereby making it easier to catch up to crafting effectively for oneself or those of one's battle class level, and to extend the level range that a given material tier may supply.
Either of those things I think would still work well now, especially if we were to just reduce the inventory cost involved in crafting, or especially crafting at different DoH levels.