tl;r You have license to be a witness with your own focus.
There are so many good suggestions here already. Can I please add that:
I don't want witnesses that are clones of each other. I'd like witnesses that bring their diverse perspectives and experiences. Yes, there are some technical requirements, but I don't expect that any human can do all the things we'd like witnesses (as a group) to do and do them well.
So, I don't mind a witness who picks their "platform", a witness that is more open about how they see the future of steem and talks about their plans for getting steem there.
Some witnesses will be more inclined towards the blockchain and algorithms, some towards reliability of the infrastructure, some towards the community. I think that's good.
I agree that diversity of talents in our witnesses is critical to the health of this community!