Extraplanar Lens + Snow-Covered Mountain and Gauntlet of Power are your friends in monocolor decks especially if you have a mana sink on your commander :)

Sarkhan the Masterless Trust me.

Endless Atlas , Thaumatic Compass  ^Flip, Wayfarer's Bauble , Hedron Archive and Commander's Sphere are all good ramp and card draw you should not overlook. They will help lower your CMC of your "aggro" deck. Most aggro decks have a much lower CMC than this, I would call this midrange.

Cool deck! You might like these: Idol of Oblivion, Neheb, the Eternal, Slumbering Dragon, Universal Automaton, Fire-Belly Changeling, Cloudstone Curio, Cauldron of Souls, Colfenor's Urn, Worn Powerstone (gets your general out T4), Coalition Relic, Generator Servant, Captain Lannery Storm, Seething Song, Irencrag Feat, Mana Geyser

Have you considered Nyx lotus and Caged sun? I feel they would benefit you immensely in ramping.

Kolaghan, the Storm's Fury is you could splash black. Together with Lathliss, total chaos!

Loved your deck!

I'll say drop the small dragons who does nothing in the larger scheme of things and add more board wipes like Blasphemous Act and Star of Extinction. Beside that maybe Solemn Simulacrum, Caged Sun and Gauntlet of Power to keep up with your high card costs.