Completely forgot that you use gold up quickly when you first start playing. You could sell off extra idols if you really wanted, but you shouldn't until you start getting doubles. Just special practice and max bond your idols for now, the Gold you get from those will be useful.
Like firehawk says, you need Rares and Super Rares really to score well.
If you're lucky you might get some rare cards when you use friend points. But it's a 5% chance or something like that...
Do you have anyone on your friends list with Ultra Rares or Super Rares? The bonus that's added to your score will help as well. Post your ID, I'll add you if you want