Best solo gold setup?

I've been playing solo a few times lately and I can do bronze solo with almost any decent survival character, and I can do silver with a few characters too. And now I'm trying to go for gold. But I'm wondering what the best way to do this would be.

I've been varying a lot with characters, but I've been playing mostly Giant and Jade versus Geth. My main question is which character with what build and what strategy is the best for doing gold solo? And if anyone have any extra tips I'll be glad to accept.

Thanks in advance