ST for Oil and Hunts for Sand. This has been my method and it seems to be working quite well ^_^

Hunts are faster and easier to get the required amount, but you have that boost to your left side gear, which is more heavily weighted. Therefore getting that side to max iLv first is better, and if you happen to do that before you get all the Oil you need to cap your right side gear, then just carry on with Hunts to cap that side as well!

btw Hunts are only boring when there are no windows open and if no one in your party talks. Seriously, with the adjustments SE made to Hunts... It's actually good content now. Once you weed out the assholes, you can have some serious fun and make a few friends while also raking in the rewards.

Enjoy!