Push pull and single ended parallel designs are the best in my book.
I would say your conclusions are correct. Different designs are offered for different jobs. It's no different than cars & trucks. SE SS is actually a SEP design. An array of output devices in parallel provides a lower output impedance, which in itself offers better performance.
Oh Yes! Differential balanced amps can be very,very nice!
![Thumbs up :thumb:](https://www.audiocircle.com/Smileys/audiocircle/smiley_thumb.gif)
Pentodes make excellent SEP's.