To take these in order: for what we're doing, I would recommend the talk I gave at Stanford about a year ago.[0] It's a bit dated (and of course we have much much more detail now), but it remains broadly on point.
For the parts of Sun that we want to take after: the good bits, of course! ;) There were things that have influenced us with respect to mission, and then also with respect to hardware/software co-design (we are, contrary to the impression you might have, doing a lot of hardware[1]). Lest I sound too rosy about Sun, it had a lot of problems too[2] -- so we're trying not to recreate those! ;)
Thank you for the kind words on the podcast -- very much looking forward to getting back in the garage and recording some new episodes!
Finally, on Spring: yes, I need to find it (we just moved) and then find a CD-ROM drive (feels easier) and then I'll get it uploaded!
[0] https://www.youtube.com/watch?v=vvZA9n3e5pc
[1] https://twitter.com/bcantrill/status/1342294298692206593
[2] https://news.ycombinator.com/item?id=2287033