You know what they say, opinions are like assholes, everyone's got one.
It is a fact that in sailing, almost any topic can start an argument. Light or heavy? Dyneema or stainless rigging? Hard vang or soft vang? Paper charts or electronic? Bruce or plow or Rocna? Ketch or sloop? Cat or monohull? Flat bottom or wineglass-shaped? Lines led aft or kept forward? Heave-to, fore-reach, set a sea anchor, run warps in a storm? Full keel or fin keel? Skeg or spade rudder? Each one of these positions has legit reasoning behind it. So you certainly don't want to take my word as gospel. In my defense I would say my opinions are generally conservative in terms of safety and also in terms of being not far off the mainstream. Both in book study and my experience at sea, I have found that by now most stuff, except for the continually changing world of electronics, is informed by lots of sea miles with lots of boats. This was not true for Slocum.

He had no one to advise him.
I do have some opinions, it's true. For example, I wouldn't be comfortable on long voyages with a boat that couldn't sail its way out of trouble, which is why I'm not partial to motorsailers, though many a circumnavigation has been successfully completed by them. That said, it comes down to the specific boat and how it's outfitted, and most importantly by a long shot, the skipper. There is just no question I'd rather be on a dodgy boat with a great skipper than a brand new, perfectly outfitted boat with a fool.