I think you guys summed it up well.
20W-40 and 10W are the only two that are now rare birds and there's really no reason to use either with the other choices available.
I basically agree with the need for zinc phosphorus additives for our engines. It was a well proven approach that worked well with all flat lifters, whether they were hydraulic or solid. I'm not against other approaches, but prefer to stick with the known for my own stuff. The SAE papers cited (but I haven't read myself) indicate oils with around 800 ppm will do the job well. With high lift cams and associated higher spring pressures, more zinc provides a little more insurance the zinc/phos will continue to have adequate levels before the next oil change. These additives do contribute to some contaminent formation, which contributes to wear, so there's no reason to go crazy with the stuff. Also somewhere above 1400 ppm, they can actually contribute to surface damage.