Ah hello sir. Absolutely don't let your players use str+ con+ dex for barbarian ac lol you will regret that! Kinda feels like you grabbed the 2024 book straight from 2nd edition play? I'm glad to see old school players and DMs still kicking it! Don't compare 2024 to the version your more familiar with, the game has changed alot even in 5th edition.
actually, although I did convert to 2nd ed AD&D when it came out, and later to 3.5. When I got fed up with 3.5, I went back to (1st ed) AD&D, which was the funnest version. I bought the starter set for 5E and the PHB, But have been unable to make sense of it. Joining a a couple of 5E games has helped some. But I am finding 6E much easier to understand.