Just got to rank 40 with this midrange list, it's been pretty smooth.
2x
Sylvan Advocate 2x
Longtusk Cub 3x
Voltaic Brawler 3x
Harnessed Lightning 2x
Smuggler's Copter 1x
Nissa, Vastwood Seer 2x
Tireless Tracker 2x
Lathnu Hellion 3x
Thopter Engineer 2x
Fiery Temper 2x
Bristling Hydra 2x
Pia and Kiran Nalaar 1x
Chandra, Torch of Defiance 2x
Fleetwheel Cruiser 1x
Verdurous Gearhulk 1x
Nissa, Vital Force 1x
Skysovereign, Consul Flagship 1x
Woodland Bellower 1x
Ulvenwald Hydra 1x
Chandra, Flamecaller (25 lands total)
6x
Mountain6x
Forest2x
Cinder Glade2x
Rootbound Crag1x
Geier Reach Sanitarium1x
Rogue's Passage3x
Aether Hub4x
Evolving WildsIt's straightforward. Against fast aggro decks, grind them out and beat with power and value of 4+ drops. Against slower decks, go to town with 2 drops and hasty vehicles.
I've included standard green pack of Sylvan Advocate and Tireless Tracker, as I didn't want to cripple myself too badly. The worst and most replacable 2 drop is
Longtusk Cub. I like playing with this card, and sometimes it can perform well, but after first few turns it's usually a dead drop.
Because of
Smuggler's Copter looting capabilities, I've decide to put 2 copies of Fiery Temper for some additional reach and value. I added 1
Geier Reach Sanitarium to compliment that. Also, some card selection is always nice.
Harnessed Lightning is a great piece of removal as well.
As of 3 drops,
Lathnu Hellion is a discussable choice. It's decent as a sweeper recovery or planeswalker revenge killer, and 2 energy is always useful.
Thopter Engineer is just good all around and synergizes with many other cards.
All 4+ drops are cards that are supposed to take over the game quickly if left unchecked, with
Pia and Kiran Nalaar and
Woodland Bellower being board stabilizers. Hasted
Skysovereign, Consul Flagship usually wins the game on the spot.
Ulvenwald Hydra is just a very solid 6 drop and can fetch
Rogue's Passage. I guess that
Combustible Gearhulk would also be a decent choice.