I feel like the best thing about this game is that it makes MGS4 make more sense. So much of MGS4 threw too much new stuff that felt out of left field, but now everything I had a problem with in that game makes sense now. I feel kinda like if someone plays all of Five before 4....that could give someone a better experience than what we did. Everything else works in release order, but 4 I think is a special case. It also creates an interesting bookend with the credits sequence from 4 being "Paz's favorite song" and...gosh I want to play the whole series like that. (With rising as an "encore" sure lol) and the last parts of 4 bookending with shadow moses would feel really poetic.
MG1 -> MG2 -> MGS1 -> MGS2 -> MGS3 -> PW -> GZ -> MGSV -> MGS4 ~> MGR
I feel like that would be a very interesting order to play the games in. You have solid snake's story that begins and then hits a roadblock in 2 when they run out of leads at the end, then you jump back to mgs3 and have this long continuous arc that sets up the events of 4 better now that we have all the gaps filled in. Also, because it's a V and not a 5, you can just wedge it down between 3 and 4. Also, gameplaywise, it felt like a downgrade going from 4 to PW, but 3 to PW feels like it'd feel more like an evolution, and then PW into V, but then 4 directly compared to V feels like an evolution that went in a different direction, while still being every bit as modern, and in some ways Old Snake has stuff that Venom Snake doesn't and could be "seen" as a natural transition from V's gameplay mechanics. (Threat Ring, Drebin Shop, Metal Gear MkII is even sort of a "buddy" character, solid eye...)
About the podcast, it's weird that none of them have played the MSX MG2. I feel that the events of those games now feel more real in the story. MG2 was actually really important to the story and this makes it feel more natural. It's interesting as a spoilercast but I really wanna sit in there and clarify things for them lol.