To be honest I tend to gear for 1 skill, for me that is currently battle chem , then what would be the other skill sets buffs I use generic buffs instead, though they offer little you can switch to whatever 2nd skill and they at least add a little extra.

Then use this gear with what ever you want to lvl whilst farming mats and materials or just goofing off here and there adding exp to various skills over time.

Then when various skills are at good lvls combine them and farm/craft gear with your chosen skill set combos.