Have you got points allocated into max fury in paragon? Your gear only has 12 max fury on it, ideally you want max fury on your gravel which would increase your cc by ~5%. For reference my barb has 185 max fury which is ~37% crit chance while using hota on top of sheet which is also around 40%, plus buffs 13% which equals ~90% cc using hammer skill (solo) in groups I have ~100% cc if a support is using 25+ ice blink gem.
I wouldn't bother with a sub-par hellfire, you really don't need weapon master with this build so it's a wasted HF passive (I'm aware you have another HF), ideally you'd want a well rolled HF with nerves of steel since it can also be used for any other build. Any really well rolled generic amulet should suffice, although a nicely rolled HF or immunity amulet would be desirable. Well rolled stats cc, crit dmg and fire dmg/ main stat would at least let you fish for an easy rift, so it gains priority over a sub-par HF/ immunity imo.
Once you get an amulet with 10%cc drop the 6%cc on helm for 15% hammer dmg. Also striken could be swapped out for taeguk, stricken will be of little help to you, the 25% dmg boost vs. RG is pointless if you can't complete the rift in a reasonable time. If you can keep taeguk stacks up, tip: you can spam battlerage to keep your stacks up, you just have to keep an eye on the amount of fury you have and use force stand still (if you don't have this bound to a key yet you should) and spam hammer skill, if it hits less than 3 enemies it starts to generate fury. It sounds like a lot of work but once you get the play style down it's really fun to play.
Sidenote: More paragon points wouldn't go a miss. Myself I'm not even going to bother pushing solo rifts till I'm at least 750, currently 660.