General Build Question [HC]

Hello gentlemen.

Im pretty new to the game, started off with a ranger in default (i think she was 40ish, deleted already) to learn the basic game mechanics and so on..then i started a marauder on hardcore (around lvl 40) but stopped playing him because of friends who played default league..i rolled a shadow and tried something like an elemental bow ranger build (lightning arrow and stuff). I like him somewhat (he's around lvl 55), but whatever...just wanted to say, that i know some things about this game now but never reached a high level and thats why i have some basic questions for my upcoming build.

I start over with a new hardcore marauder and wand to end up with righteous fire.
Since im neither a real casual nor a pro this will be somehow tricky for me too achieve, because i think i will have my problems getting Rise of the Phoenix or other important items for this build.
Too make up for that i want to start off with immortal blow (eg. with melee splash etc.) and try to come up with a build which combines these two builds. In other words i want to come up with a pretty tanky build which gets as much life regen as possible and which focuses on immortal blow as primary damage source. When i get the right equipment i can easily switch to righteous fire.

Of course i started this thread because i want to hear your opinions about that but i have some further questions:

- Is it possible to use the passive Blood Magic with righteous fire or do i have to figure out the best way to get rid of blood magic without using too many refund points when im "rightous fire ready". (I definitly want to use blood magic and if possible without skill gems)

- Do i need a physical damage ability as an alternative? I never did any maps because my chars are still too low, but i read something about maps where all mobs are eg. fire resistant. Or would another elemental dmg type be enough? (eg. Glacial Hammer)

Now i wrote too much shit and forgot my other questions i had. i have to edit this thread soon :p

I would appreciate any hints you got for me about this topic :) Thanks in advance.

Righteous Fire isn't really new player friendly and would advise against it.
But with that said, I'll answer the questions:

1.You shouldn't use Bloodmagic gem or the passive for your main attack. You will use Blood Magic Gems or Equips to use your Auras. You want to get low life to get some of the buffs from the uniques. All your attacks will come off of the mana pool. Your life becomes your ES.

2. If you're a caster, then no. Just cast whatever. Since RF gives you a spell boost, your spells will do enough damage to roll stuff over (with the right gear too). If you are Melee, you should always have a single target attack anyway. Don't worry about the Resists of the mobs as you should be using a Curse too.