I'm predicting that Hard Mode is going to be more than just "less random drops and you take more damage." Mainly because from what I've heard, Breath of the Wild is supposed to be a hard game already, having that old school jRPG style of "Looks like you walked into the wrong area, mother fucker" and getting one-shotted by stuff you're not ready for. It's sort of already supposed to be hard mode. So since this is behind a paywall and is taking some time for them to develop, I think that heavily implies that it's going to have a lot more effort put into it than what they did for the likes of the HD remakes and ALBW, which might mean smarter AI and putting more challenging enemies in different locations that you're not used to, and it may possibly mean that the main dungeons might be different and more challenging, like 2nd Quest/Master Quest.
I'm not too keen on DLC, but like, keeping things in perspective, when has Nintendo really ever released a game that was incomplete at launch at made us wait on DLC for the full experience? Mario Kart 8 still had an amazing selection of tracks, Smash 4 still had a great roster and stage selection, and Hyrule Warriors still had an absurd amount of content, all without their respective DLC. Breath of the Wild is a full- a massively full- adventure, with or without it. I don't see Nintendo treading toward the ways of say, Mass Effect 3. I feel like it was either this or the game get delayed again, at any rate, and I don't think they could count on that.
People sorta act like DLC is the boogeyman, but have y'all played Bethesda's games? Because their games usually have really good DLC, well worth the price. It's not always this inherently evil. corporate greedy thing designed to squeeze every last penny out of you, shockingly developers actually use DLC to give you more to do so you can revisit their game. Sure, we'll see how it goes when the DLC rolls around, but Nintendo's had a pretty good track record with it so far, so I'm not expecting it to be all that disappointing. The only thing that really irks me is that the Special/Master Editions of the game don't give those buyers this DLC. Sure, they come with a lot of cool physical goodies, but those bundles were expensive. Would've liked to have either one, personally, but sort of glad I didn't dip extra for either one...

