i am not here to provide answers.. i am here for more questions
the (4) though i can answer
what is pure petmancer stat distribution? some people make it pure int to equip a pet buff staff.. but i think that would be a mistake because you will end up with much higher int than you need.. i have seen str+dex+int petmasters with dex being the highest endgame to get as much DA as possible.. that one i can agree with.. but my skinchanger, the closest i have to a pure petmaster, is str+dex+int until end of epic and then start of legendary onwards, i pumped only health.. but that is because i did not rely on DA for survivability but briar ward + damage absorption combo.. something only possible for a skinchanger.. for what it's worth, i think stat distribution for a petmaster should be str+dex+int because since you will not deal damage anyway, you are better off equipping the best items you can find whatever the requirement is.. but do not start hybrid stat right away, start with 1 or 2 stats except pure dex
random thoughts: i think the best character for a HC run would be something you enjoy playing so you can focus on that character only.. i play many characters and when i focus on one character, then switch to another, there is always a time for adjustment so i can get used to it again.. that time for adjustment can sometimes lead to a death.. there is also the case for my mage Haruspex.. it went really smooth i could've played it no deaths.. until i got bored playing it because it's too repetitive.. when i got to 3 Fafnirs, i found it enjoyable again i couldn't resist the urge to play them like 10x.. boom 2 deaths
.. i don't regret it though
i do believe that there are different ways to building a class and i do like that you are considering different builds for a ritualist.. i do not believe that there is a hierarchy to class builds, something i think many people will not agree with.. i think some are just harder to build but not necessarily better than others.. what i mean to say is i think a ritualist is just as good as any class for a HC run so long as you can find a build and playstyle that suits you along with a good gear set-up
now for 4th question, i think that would be difficult.. distort reality has 12 seconds cooldown and at 80% CDR, you can only get it to as low as 2.4secs and the damage would still be not enough at least for a str build.. distortion wave would be better for that because the first 2 skills scales with str and the reduced armor really helps.. the problem is the energy cost is HUGE for a non-int build.. you can wear golden fleece and seal of the high priest but would that be worth it for a physical damage build? i don't think so.. i think the best build to utilize distortion wave is str+int and i think the devs made it that way as evidenced by the fact that the first 2 skills scales with str but the 3rd scales with int.. this one i can say from experience.. my Haruspex has no other attack but distortion wave and my first dreamkiller, part of that theorycraft is reducing armor with distortion wave then letting traps deal physical damage.. my bracers were also twisted coil of the parasite to reduce resists via throwing knives
finally, i think character building should be free and not be bound by any rules so please feel free to build a str build dream caster and prove me wrong
i promise i would not be mad.. in fact, if you succeed, i would be happy because there is another ridiculous build.. pls share it with us if you decide to do so
edit: hey right maybe it's possible with tranquility of water and sanctuary, then plague of course.. i say go for it