I'm going to agree with @bigtom13 here @brittandjosie - Witness voting is incredibly complicated and we all have to respect that ultimately it is putting "Your Investment" in a cryptocurrency toward an account you hope will make your investment grow. So while currently we have 30 votes - if you only believe 5 accounts are going to help you Investment - then for sure you should only vote those 5.
I use all 30 of my votes, but that is because being a Witness I appreciate the costs involved - running servers, paying for them, the time taken to get the server running and the time needed to keep it running. Outside the top twenty I doubt any Witness is covering costs, I know I have never even broken even - and that's before I added two new servers to run my full node https://api.c0ff33a.uk
But as a Witness I am not running these servers and supporting the blockchain to gain rank - I'm doing it because I believe in Hive and the Blockchain, I have made many many good friends on here over the last three years and by running these servers I support the blockchain, my investment, and the friends I have made.
That said I really appreciate every single Witness Vote - I have 999 right now and to me that is an incredible number of people supporting my efforts.