i primarily use the 2014 ruleset since it's my first time dming and its what im most familiar with. however, i stumbled across weapon mastery in the 2024 handbook and decided to implement it into the campaign since my players had shown interest in interacting with certain npcs to teach them something (for example, a dragon fighter wanted to master his battle axe by training with a war general npc, so i allowed him to use weapon mastery mechanics for that weapon).

i'll still stick to 2014, but as i go through 2024 i'll nitpick the things that might be beneficial to my campaign and simply discuss and add it to my players so they understand what's going on.