That's great though, you're using the platform, that's always good :) Yeah there is, there's a thing called voting power, that needs to be at 100% to give the full power of a vote. Each vote reduces the power; although off the top of my head I don't know the exact mechanics of it sorry. There's loads of steemit articles on it though, try a Google search :)

Steempower is good but, and I think it's a massive but, you need a LOT to have any real impact, and you also have to lock it away for pretty much 2 years. Unless you've got a few spare Bitcoins I've always considered it better to invest. Entirely up to you though, I read somewhere you get interest on Steem Power, so if you're super confident Steem will increase it could be wise.

As for DGB I hold some myself, but I'm not aware of anything that would make me double down on it. Do you know if there's any news coming out soon?