I've recently returned to the game, and I will admit I tend to spend money. In two weeks I jumped from 3K rating to 15k.

Lets assume I was spending about $100 USD every couple of weeks at 50% (1700 gems), what is the best 'value' for gems spent? I'm just looking for different opinions.

I currently have 168 dragons, so I have a long, long ways to go in my collection.

@thomas-b-settle I am not spending money. So I always saved my gems for buying new islands. Because we need a lot for these. First thing besides this I would suggest is to upgrade the hatchery, buy the breeding tree. Plus you can use gems for heroic races or to speed up other things for events to get best rewards.