Being a witness is super ridiculously hard and time-consuming. I think your reasons for voting witnesses are pretty sound. I definitely believe in meritocracy. You should vote your conscience and for individuals you think are helping the community. For a bit more insight, you can also check out https://steemian.info/witnesses
Besides representing steemit and steem, witnesses also produce blocks by running a server. They get paid for the blocks they produce. The higher up the ladder they are, the more blocks they produce. This is evident from the link I mentioned. It might not matter to you, but it matters to some. The top 20 witnesses produce a block about every minute and get 0.2 SP block. That's 1 SP every 5 minutes. It's important because these witnesses use that to pay for upkeep of their systems and the work they do for steemit. Just like voting for authors, your vote can be used to adjust a witness's income to what you think is appropriate.
Some witnesses are passive earners and just run the bare minimum for a witness server. Other witnesses are very involved in the community, run really powerful nodes, and/or write software to help the blockchain.
I myself pay out to bidbots, but I do one post/day and try to keep it below $50 payout. The point is really just to stay relevant. I also will post on #utopian-io which supplements the need to use a voting bot because @utopian-io will vote for my post.
Well, sir, you have earned my tiny witness vote. I think you are here for the good of steemit and have our best intentions in mind. Thank you for all the hard work you put in. Without people like you, this place would come to a grinding halt.
Much appreciated! Thank you for the encouraging words