Perhaps the best way to look at it is that TSR developed more and more interesting, imaginative games through the 80s and 90s despite the executive structure of the company.
I’d have to say three books:
All-time classic. Even if I never used it much, the high Gygaxian prose is incredible.
This might be my favourite. I played 2e through high school and Uni. I was at the age that when I bought this I sat and read it cover-to-cover.
This is another classic...
We’re a group of 4 including the DM, with an “everyone plays or we cancel” policy. Usually someone has something else going on, or else it’s an illness.
I have a set of metal dice but I generally use my regular dice for most stuff.
My current go-to d20 is an ancient rounded thing is swirling blue - it looks like that RPG Network “earth” d20 logo.
I don’t know if it’s exactly what you’re looking for, but Dolmenwood has that faerie-touched British isles feel, and it has alternate magic systems complimenting the more standard D&D style of magic.
I have a couple of the old editions - brown covers and 25 (rather than 20) chapters. Not only does some of that not hold up, at least one book was completely rewritten. I can’t say why, but the original had a ton of stuff that would cause outrage today.
This is a hugely important point. If people are playing on VTTs that may be based specifically around a particular rule system, then the ability to customize certain things around the “table” could be limited. This would be an argument that what’s published does carry weight over individual...
Mike @SlyFlourish mentioned a series of videos featuring Peter Adkinson where they play each edition of D&D. Each session is preceded by a panel discussion of the original creators or others who had been around for the development.
I’ve not seen them myself so I don’t have the link…