As a caster main, I'm trying to keep my weaving about equal with my conjurer. Your best bet, in my opinion only, is to become a materia melder yourself. That involves not just crafting to be at high levels, but gathering too so you can support the crafting jobs with crystals and catalysts for melding.

As stated above, there's no negative to putting materia into early gear. You can just convert the materia-laden gear into the new gear, and equipment spiritbonds so quickly that you may even find yourself with more materia than you know what to do with. Of course, this is the anti-immediate gratification method or method for those claiming they're going to die in a few days (i.e. short on time), so take it with a grain of salt.