Variable Command

The Variable would store and modify data (like the scoreboard command), but it will be a more user friendly option. It would have sub-commands like, "add, remove, modify, set, score."

There would be 3 types of Variables, global, entity/player, and team. Global Variables would be tied to everyone, Entity/player variables would be tied to each individual entity/player you give it too, and Team variables would be tied to each team (through /team command).

To modify a variable you would have something like this, (ex. OnKill, Getvar[var=x] + 1). There would also be triggers that activate when a variable gets to a certain number, (ex. /execute if variable x @p greaterthan 5 run kill @s).

It has the ability to be tied to a score through the scoreboard command. (ex. /Variable set x getscore players @p).

There are other posts that say basically the same thing, but personally this would be a nice edition to Minecraft. This will also help creators with a better way to store and modify data.