Yeah I think there are some good ones to support. I haven't supported any until recently but I have been pretty picky, so I want to be careful about who I do throw support to. We do need people to create blocks, do validation, and run a node full time which can be costly.

Also from my understanding, code changes are not adopted until 67% of the Witnesses apply the updates on their nodes, so you should support the Witnesses that you think will go the direction that you would like the most. You could also become a Witness yourself, but to do that you have to be approved voted in by the community. The more Witnesses we have, the more distributed it will be.

Not sure if you have seen this or not, but I found it helpful.
https://steemit.com/steem/@steemitguide/steemitguide-what-is-a-exactly-is-a-steem-witness-and-why-every-user-should-vote

Thanks for the comment!