For #2 what you need is just budget $500 to get everyone a podcaster mic and a pair of open-back headphones for calls. It gets rid of the "half duplex" thing, and with the headphones plugged into the mic as a monitor you hear your voice in a different way and don't speak so loudly reducing fatigue a lot.
For #3 I just recommend pair programming. Pairing is already a skill that needs to be learned and remote pairing is a more difficult one. But the tools for it are better than they were a few years ago and are good enough, and it's an excellent venue for naturally exchanging a lot of that sideways knowledge and mindset that makes more experienced engineers so effective.
For #3 I just recommend pair programming. Pairing is already a skill that needs to be learned and remote pairing is a more difficult one. But the tools for it are better than they were a few years ago and are good enough, and it's an excellent venue for naturally exchanging a lot of that sideways knowledge and mindset that makes more experienced engineers so effective.