I'm on the fence, but seriously considering HC from 10+, with the understanding that if I create any softcore characters, I can only get them up to the content I've already explored under my HC character. (for the first playthrough, as I want to unravel the storyline only as fast as I'm able to progress in HC.
For now, I'll faceroll Normal mode on SC first just to see the content, etc. Though, a person could probably facroll Normal mode on HC just the same, I don't want to slow my roll on enjoying the "maiden voyage", if you will, with the added push of trying to stay alive. Also, I don't want to get to Act 2 or 3, do something stupid and have to start over, again, in my first time through the game.
Now, once Norm-SC is over, then yes! Let's fail in Norm-HC all I want!
Also, with all the hype surrounding the challenge curve through the difficulties, I'll probably do the first few quests in NM-SC too just to identify exactly what change to expect in advancing difficulties for a character that just defeated Norm Diablo for the first time 3 minutes ago. I don't want to go to Nightmare and get one-shotted by the first zombie. If that all checks out, it's purely HC from there on out for me.
I'm gonna do inferno on SC before starting my first HC char. If everything goes as planned i will be streaming with 3 mates from a gaming cafe in stockholm sweden while aiming to clear inferno as one of the first in the world.
Playing HC as first will leave you feel gutted quite often i think: imagine getting to level 40, dying, and now, you can't even see the next content of the game, instead, you'll have to relevel from scratch and do all the stuff you've seen already again untill you can progress and see content you haven't seen yet.
I think that alone might ruin it for me as a whole, i'd probably say "fuck it" at that point.
Playing hardcore as soon as humanly possible (I still need to plan out the quickest way to get to level 10). Going through the initial story line in Normal mode will be very exciting as well as more thorough, as I will be searching every crack and crevice of the map for gear, money and monsters to level me up. I'll probably be playing through certain parts multiple times to gain more of an advantage with gear and levels. Going into Nightmare I want to be at least 5 levels above the content and extremely well-geared, and doing so will allow me ample opportunity to enjoy the story-mode in Normal.