I see a lot of people complaining about having too many gems and too much gold. Keep them. Keep all of them. With the advent of legendary gems in 2.1 and lots of revamped rings and amulets you're going to re-roll A LOT of jewelry, so you need a ton of gold of gems. Do not think that 1000 gems is a lot because it's nothing once you found this perfect new ring and can't get a socket on it after 50 re-rolls.
Kadala is not about finding "random loot" but only for gambling a specific item. A similar idea has been proposed recently. Not too keen on it. But I think Kadala is too good in general (yes, she can be a bitch at times, but anyone remember her father from D2? THAT was gambling, Kadala is a safe investment if you gamble the right pieces).
Also, Flawless Royal gem costs 9.8m gold, not 20.6, and only if you start from Marquise... but you pick up a few Imperial on Torment as well, so it's even less. And with the new Vault introduced in 2.1 gold is not longer an issue, you can farm it now (more or less).