Question: Best use for each currency

The weekly bonus to get an extra dispatch just expired for me, but I'm wondering if it is worth it? Is there are good guide to know what the best use for each currency is?

Right now, this is what I'm doing:

Gold: Buy the 10 Green Gem each day. 1000 for the bone collector each week. And upgrading gear. Stay at the cheapest room to save money.

Green Gems: I've only used them for the weekly dispatch increase and for banner pulls. Is there a better use?

Guild points: I have over 10,000 but I don't know if I should go for 1 Legendary bones or 10 regular ones. Using the regular ones to level up my current legendary characters seems to be working, but maybe that Legendary is just so much better?

Actual Cash: I bought the weekly sale item for $2.19 (Canadian) which was 300 green gems and an XP book I will never use. I read that's the best deal in terms of cash for pulls and this game is definitely worth more than $2.19 (Canadian) a week.

Any advice would be great.