Let me ask this. With your method of either having shared loot, or personal loot optional would the same amount of drops occur if it were only one, or the other?
Example:
8 player game. All have checked shared loot. Each of you kill each end boss on every act(Andariel, Duriel, Mephisto, Diablo, Baal).
Example of drops that have value that dropped in this particular game:
Andariel - SoJ
Duriel - SoJ, Shako
Mephisto - Um Rune, Occy
Diablo - Ist Rune, Ormus’, Shako
Baal - Tyrael’s Might, Um Rune
In this example there is a total of 2xSoJ, 2xShako, 2xUm Rune, Ist Rune, Occy, Ormus’, and Tyrael’s Might. That’s a total of 10 items of value that dropped during this shared loot game.
Now, let’s try to input same 8 player game, but say instead they have checked personal loot. Would there still be the same 10 items of value that drop, but it depends on who gets it, or would each person have a chance at getting more items of value since it is personal loot?
If the shared loot, and personal loot of this example still get the same amount of items per game then it would be reasonable to have either as optional, but if personal loot allows for more loot to be dropped in total then there would be advantages for more loot if personal loot is checked. Also, it would make it to where there would be too many items of the same for trading, and nothing would be rare because everyone would have the same thing. D3’s personal loot makes it to where you find everything in the game just about within the first day of playing. D2’s shared loot makes it to where sometimes you can’t find a certain item for days, or weeks, or months, or even years. That’s what makes it fun, and unique.
So, conclusion is that in my personal opinion is to keep the loot in D2: R the same as original D2, shared loot. Although personal loot seems like a nice QoL, it strays from the preserved part of D2 looting.