Well, it's been a while. Thought I'd start a thread to see if any has developed some longer term insight, now that the skill has been out for a bit.
For me, I've tried two strategies.
1) Minimize use of shards (and thereby cost), no matter how long it takes to collect the seconds. Marigolds and abyssal charms were probably the slowest things to collect (for me at least). This took forever.
2) Maximize exp points on charms. This means, make the highest exp. pouch possible for a given charm, no matter what the cost in shards. This is faster, until you run out of money. Then it slows down too.
3) Chuck it all and work something else, until that major update they're promising comes out. This is my current strategy.
What about you folks?