Why is my value still 30$?

The more giveaways you make, the more giveaway slots you will have. Also, if you giveaway enough non-bundle games you can get full value for your bundled giveaways.

Effectively yes, until you give away a non-bundled item (an item that doesn't have a * next to it in the 'create a giveaway' list), at which point you can get more CV from bundle items. It's all explained in the FAQ

Yes and no. If you giveaway a non-bundle game, it will raise 0.2% of Zombie Driver HD Soundtrack price + the non-bundle game.