OK, I’d also do this…
Gear
Helm - put a diamond in it (Cooldown Reduction). CDR refreshes leap sooner, leaping keeps you alive (set armour boost).
Amulet - re-roll attack speed for a socket and put another legendary gem in that. Also look to do a Hellfire Amulet run for a better replacement and free passive.
Shoulders - re-roll life for CD, see helm.
Chest - re-roll Furious Charge damage for anything, probably Vitality
Gloves - re-roll resource cost for crit damage
Bracers - fine as is, but replace for anything better - leg with a more beneficial effect or anything with dual crit.
Rings - I am presuming you rolled sockets onto them, but I can’t tell. If the sockets are native, re-roll the missing crit stat onto both. Ideally you will replace them with legendaries, but if you have none, craft yellows until you get one with a socket and one crit affix. Roll the missing crit affix onto it for a dual crit ring. Crafting dual crit rings is pretty cheap, gems will be your limiting factor.
Pants - re-roll regen for vit.
Boots - fine
Weapon - fine
Gems - OK. Get key gems to top tier ASAP - weapon and helm. Ultimately, you will work towards more rubies than diamonds for chest and pants.
Paragon Priorities
Movement Speed, Str, or Vit if desperate
Crit hit, crit damage
Resist All, Armour
Area Damage, Life on Hit (prioritise LoH if desperate)
Skills
You need to build fury quickly and spend it faster - spending fury resets leap, leap keeps you alive.
Your generators need to be generators first, they don’t do your damage anyway. Switch Cleave over to Reaping Swing, or switch to Bash Instigation. Frenzy Beserk is another option, but probably not with a slow 2-hander. I’d probably stick with Cleave for the moment.
Ground Stomp and a secondary generator is pretty fine. Consider switching to Deafening Crash, however, for the reduced CD and damage mitigation. That said, the Wrenching Smash pull is a good pairing with Cleave for generation if you don’t need the extra mitigation.
Seismic Slam is groovy, that is your spender. I’d probably switch to Permafrost for mitigation or Strength of the Earth for health recovery. Leap, Ground Stomp, Cleave, Slam, Slam, Slam, Cleave, Cleave, Slam, etc, until Leap resets, rinse repeat.
Earthquake - switch to Chilling Earth. Whenever Earthquake is on your bar, whatever rune is selected will proc when your Leap causes Earthquake. Chilling Earth is great damage mitigation and you want to trigger that mitigation every time your Leap comes off cooldown. Alternatively you could use the Cave-in rune for pulling with Earthquake and use Deafening Crash for the mitigation. If your mitigation is in good shape, just for for the extra damage of Molten Fury.
Avalanche - looks fine, proc’d with your belt and with a good damage mitigation rune. But, I’d consider swapping it for Warcry for the generation and damage mitigation. Pick a rune that fills mitigation gaps - more armor with Hardened Wrath, Health regen with Invigorate, etc. Avalanche does do some damage, but ultimately you want your goal to be resetting Leap as soon as possible to trigger armour boosts and more Earthquakes, particularly while you don’t have Lut Socks.
Passives look fine.
Legendary Gems
Your priorities should be Bane of the Trapped, Bane of the Powerful and Esoteric Alteration. Two damage multipliers and one damage mitigator. If you have all of those, put them in and get them to level 25 ASAP. If you don’t have them, run some more GR’s. GR level does not matter, just get the gems as quick as possible.
Cubed Items
Armour and jewellery slots are fine, until you get those Lut Socks for the armour slot A better weapon ability would be great as the Decimator ability just won’t be contributing all that much.
Things you want to keep an eye out for and not just salvage
Focus, Restraint, Lut Socks, Band of Might, Girdle of Giants, Nemesis Bracers, Broken Crown, Goldwrap, Ancient Parthan Defenders, Bracers of Destruction, Blade of the Tribes
So a bit more crit and cooldown, get another couple of legendary gems, change a couple of skills for mitigation and faster leap reset and I think you should be good to bump a couple of torments.