zipec

Solid deck. I played similar one, more on the control end of flickers. With Stonehorn Dignitary, Wall of Omen and Solemn Simulacrum.
Restoration Angel is an obvious (although expensive) choice, also Conjurer's Closet and maybe Soul's Attendant or Auriok Champion instead of Suture Priest to stick with humans.
I dont like your artifacts though.

If you want some sideboard help, what about Slagstorm or even better Bonfire of the Damned against white weenie. It ruins their tempo much more than yours and clears all those pesky 2/2 first strikers who make life of your Ball Lightnings so difficult.
Nice deck all around.
PS: Keldon Marauders dont like Torpor Orb in your sideboard :-)

Thanks for excellent ideas.
I will consider more Loyalists, but I like to keep Guides, their early pressure is just amazing.
As for Raid Bombardement, I like the idea of Hellrider on enchantment, but there is Krenko, Hellrider and Tuktuk the Returned and everyone else could be boosted by Chieftan and/or Curse to the point where Bombardement will not trigger.
Browbeat is great idea. I will sideboard two. Also it reminded me of my favourite Reforge the Soul (sideboard 1), which is good against control as it regains your momentum. But I will keep Combust because it serves different purposes.
Great, Sideboard is now finally starting to look good.

Magewright's Stone looks nice in Krenko EDH or some kind of Krenko combo decks, but I am affraid in aggro where it can target only Krenko it would be dead draw more often than not.

Agreed, Darksteel Myr is a bit off :-) Maybe 4 Avenger of Zendikar?
I like the Epic Struggle+Avenger of Zendikar+Conjurer's Closet combo.

I concur. This deck needs some early protection and more ramp. Mana elves sounds good. Also, consider playing fewer Leylines of Anticipation (possibly 2), you really dont want to draw multiples.
Some duals could be usefull. If you need forests (because Beacon of Creation) use Breeding Pool instead of Simic Guildgate.
Another thought: Conjurers closet is nice, but it really works well only with Avenger of Zendikar, its useless without him. Either add something else with ETB or remove it. Already mentioned Primeval Titan sounds solid with the Closet.
Another problem: Fog. It may help you survive a bit longer, but its very temporary, also it is anticombo with Unexpected Results. Consider instead maybe some token/land/draw creatures, e.g. Jade Mage, Coiling Oracle or Yavimaya Elder.

Thank you for your ideas. In fact I used to run more burn-based goblin deck with Grenades, Arsonists and Reverberates (when they were standard with Krenko). It also worked, but I like this creature-based version more. The Hellrider is awesome and although not a goblin he has an awesome synergy with them. Together with Spikeshot Elder and Five-alarm Fire he offers similar reach as Grenade would.

Ideas: Nether Traitor, Dimir Infiltrator

3 Kuro's Taken -> 3 Vampire Nighthawk

3 Last Gasp -> 3 Go for the Throat (preferable) or Doom Blade
4 Typhoid Rats -> 4 Tormented Soul
3 Tidehollow Strix -> 3 Baleful Strix
4 Levitation -> 2 Vapor Snag & 2 Artful Dodge
1 Ninja of the Deep Hours & 1 Throat Slitter -> 2 Mistblade Shinobi

Ideas: Invisible Stalker, Inkfathom Infiltrator, Vedalken Ghoul, Chambered Nautilus, Alley Grifters

Thank you for your thoughts. Restoration angel is a good idea and I would like to try a few, but they are hard to get. As of cloudshift I sideboard one but the problem is I can't exile artifact (Contagion Engine or Spine of Ish Sah) with it.