Newb Incinerate tank HC help/ talk

Hi, fairly new, about a month in. Wanted to do a fire witch for the new season, dabbled in ignite for a bit at the start. Then went hardcore. It's just necessary. Checked out the Incinerate build and thought to myself how in the hell could that be HC viable. Though of course I'm hardly an expert. Went to the passive tree which is apparently interactive, nifty. Noticed you can Go straight tank at the expense of only area damage and mana regen mostly. Like all the way down to the guard skill armor buff at the bottom of the skill tree, with 2 +150 armour passives along the way callibre tank. Since incinerate is already damaging a decent sized area and doesn't cost me much so far, I am doing just that.

My only experience in getting to act 4 so far is in tanking so forgive me, then I learned I was good to go for a few more acts had I not died from darkness(really? that mining guy wasn't just trying to scare me?), when I decided to play through quickly a bit until the new season started in a few days. So far it is great. Just 16 passive points to go until I am done with defence and on to fire dmg/ golems/ channeling. Read up on a tank witch build just now but couldn't understand much of it. Acronyms and end game jargon and gear I have yet to familiarize myself with. But I did see it might be a good end game thing too. Any build page looks like french when you aren't already a level 100 with a full box of stuff.

So far I have better offence than my last guy, a bleed barb who had more offence invested at this point, being as it is closer too the armor passives, and a better weapon. Have been sticking to Armour/Energy Shield gear. Though I already plan to switch to full armour chest and spell damage shield for mid game. Should have already given i use red gems alot anyway. Amazing move speed
unique boots with only ES and amazing speed at full life that will be tough to let go.

Skills are Incinerate with 3 supports, scorched ray totem, Both are in 4 links with the best supports i could muster. armageddon meteors with a sweet faster/more meteor support and another. efficacy and unbound ailments mostly for those 3. summon angry fire skull dude, with 2 minion supports, which will be a golem asap. fire dmg aura and mana regen aura. Molten shell with duration support. Flame dash. Not too concerned with skills and supports, i will have the suggested ones and a 5 or 6 grouping on a piece of gear or 2 at some point. (one question, will try the infused channeling support I guess, but am I missing something or is it not that good? does it level well? the defense seems oddly specific and I don't understand it, would it only help me against fire damage?)

Super easy to kill everything up to the end of act 3 so far, super easy to keep resist maxed and dmg reduction from armour around 75% right now, more like 90 in a few levels with molten shell levelling and the passives, great for levelling safely. I could pick any of 3 skills to kill everything but the bosses by themselves. Armageddon looks best really, but I imagine not so much vs bosses or later on maybe.

But mid to end game, I assume attack speed is what I'm after eventually, and then mana because of it, I assume I'll lose some of my armour to go for a 2 handed 6 socket weapon or a perfect for the build unique that lacks it, or just kind of stagnate I guess as the armour total becomes less and less effective through the levels. I could still muster lots, and may even be satisfied with around 55% dmg reduction and a nice use of a granite flask and a great molten shell. I may even switch away from armour with a respec at some point. Stretching the passive tree out that far isn't exactly a good idea one would think.

Sorry for being so thorough, I guess what I am after is thoughts. I know this is a solid plan up to level 55-60, but am concerned after that. So some experienced thoughts on the playstyle of incinerate without armour, just how you stay alive when it seems to me you could be one hit multiple times a map. Is it really as simple as a guard buff and granite flask and skillful avoidance? of course the best defence is a good offence and vice versa, but on hardcore eventually most of us normal folk would die right? How would you weigh dmg reduction vs dmg? I like this game for it's versatility and users choice so far but wouldn't mind some beginner speak thoughts on it. You know, incinerate, it's possible tank version and many secondary options. Whether it is a one or the other, or an anywhere in between kind of build. I'm about to ascend after maybe waiting a few levels to finish act 3, so any thoughts and advice could be awesome before making that choice possibly. Armour is huge for the end of act 3 on HC IMO but after that I'm all ears.