Not to be rude, but your impressions (opinions) kinda suck. I'm not a huge fan of playing barbarians because I have my own preferences, but removing immunities in this game is a horrible idea. You can get up to 100% pierce for regular monsters and 199% for some bosses. Removing immunities would make the bosses totally pointless as a boss. There are skills that can remove/"break" immunities, and some builds emphasize those heavily.
How do Snake and Eagle stances not fit with barbarian? How do wolves not fit? What elementals do barbarians have? They can summon Ancient Spirits, but no idea where you're getting elementals from. You gave very undescriptive impressions for these points.
Having pre-requisites is the entire concept of Diablo. What would be the point of building a character if you could just say "Oh I want this one, but don't want to work for it."
I think you need to play through the full game instead of just the beginning and viewing the skill tree to make an impression about this game. Many new players have done the same as you and complained about similar things, only to find out that they just never put the time in to try to understand how skills and builds can work together.