If you have a witness running beside you at your desk and you can see the logs running all the time (and immediately when they go down) you are much more connected to being a witness than having it run on some "cloud" server somewhere.

I disagree, I can see logs from anywhere in the world at similar efficiency. While I am not against having your own equipment what so ever, I do have concerns running critical servers on a home network. Granted not everyone has to deal with snow I won't run even simple services like Poshbot on my home network as I don't trust a home connection being available. This is just my own opinion.

Why do you suggest that I would be missing blocks with this setup if I made it to a top20 witness slot? I can always add a second backup witness node to provide further redundancy if necessary. I've got heaps of PC parts lying around. :-)

I see no problem with that hardware, but you did mention a 9 year old laptop. The thing is, running a witness is a lot different than replaying one. While we do have the ability to do snapshots now, it can still take hours to transfer block logs and snapshots even with 1 Gbit Internet connection. The real problem comes during hard forks and emergency patches, you won't have a snapshot to rely on, and will need to do a full sync, witness nodes and API nodes.

Most witnesses are no where to be seen when critical shit happens, the witnesses that are and have the hardware, Internet, and knowledge to support agile recovery are who I want protecting the Hive blockchain. Unfortunately, this list is rather tiny and doesn't reflect in the witness rankings.