I find Retainers to be a good way of maintaining a stock of materials for whenever the sudden urge to craft comes along.

Rather than hunting for 100 Chimera Manes, you can over the course of a few days, send the Retainer out for them, store them, and then craft with some/all of them. Then have your Retainer resupply you with them.

Or you can just send the retainer out on Quick Ventures or 18 hour Ventures that you could before. Of course, at level 60, the Retainer has access to all that higher-than-i150 gear, you know. That should have some impact upon the quality of junk that your Retainer brings back on those two Ventures.