Nice review Baard!

We also really like Bahia de la Chiva.
We had bioluminescence around the boat the night we anchored there, and there is very little light-pollution to get in the way of seeing it.

We've anchored in Bayo Flamenco three different trips now, and have been fortunate to not have a ton of swell, but we usually go in the summertime.
That said, the swell does get in there, and monohulls would be thrashing around. A big cat like Cuvee doesn't move much.

The thing I love about SVI anchorages is something you already mentioned. Much of the traffic is local powerboaters from Puerto Del Rey, and they are usually gone by 4pm, sometimes leaving the anchorage totally deserted. So don't despair if you arrive at 11am and are 4-rows back from the beach. Be prepared to move up after the day-trippers all bail out.