It's a remaster. Nothing should be added. That would be remake territory. The while point is to modernize an old game to take advantage of newer tech like better graphics, better networking, and such. No reason to add anything. They could be there is no need to on a remaster.
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Never went online with D2. My experience was different. Sure I went at my own pace, but the fact that droprates were designed around trading, and were pretty low for both offline and online made me frustrated.
I remember a 2 week period were I would play after work for about 2 hours a night. I saw not 1 quality upgrade the entire time. If anything, rates should have been, and should be tweaked a bit for offline play.