Really, you need to think of single-player and multi-player D3 as two completely different games.
imho, the difference between single-player and multi-player is much greater than the difference between Softcore and Hardcore.
If you enjoy single-player (like I do), then play it. But don't look at the multi-player people and get angry that they are vastly more advanced than you. That's like a Hardcore player looking at a Softcore player who goes full glass cannon and dies a lot, and getting angry that you can't do that in Hardcore.
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