Well, in order to know how to help you one would need to know what you "might" have done to cause Google to want to sandbox you.
Always but always - you can ad high quality backlinks to your hubs.
Here is what I would do:
Join InfoBarre - write short articles there (five hundred words is good) that summarize a hub, and link back to HP with one backlink per InfoBarrel article.
Blogger.com - do the same thing
Xobba Tribune - do the same thing.
Any revenue sharing site worth a dime will allow you to do what I've described above, and will give you high quality "dofollow" backlinks that will, in time, un sandbox you, and provide you more traffic, and additional platforms for publishing success.