Almost all of the problems that you mention here are addressed:
- Opt-out rather than opt-in travel insurance is now opt-in
- No seat is selected by default, therefore no seat selection charges are made by default
- Spirit is (subjectively) very clear about their bag fees
The one point that sticks even today?
- Spirit is not clear that you can save $17/one way ticket/passenger by buying at the airport
On the whole, though, there seems to have been a massive change in their marketing. They seem to be trying to communicate to customers what the value proposition is and what to expect when flying Spirit. They also say they've been retraining their staff to be more respectful; I have limited to experience in this regard, so I can't really comment on how things have changed, or not.
Ok, this point stands: "I’m long on record believing that Spirit Airlines is a carrier I would never want to fly..."
But has this part become more nuanced, "and one that I wouldn’t recommend flying"?
I realize I'm citing a post you made three years ago, but Spirit is the leading LCC in the US industry. Making these changes is significant.
Have a great day, Gary!