1. Play 3c or more, most of the time. Some colors are quite niche, and it’s necessary to strengthen them (but if you’re in Izzet or Dimir, you should be fine).

Bant: solid control deck, can occasionally be lands.
https://cubecobra.com/cube/deck/62abbbac88da1a0ff840635a
Esper: absolutely fantastic control, probably tier. No fringe combo is in esper.
https://cubecobra.com/cube/deck/62abc8c988da1a0ff840b7fb
Grixis: Absurd. If it’s open, you should be drafting it. Control, combo (Kiki-Jiki, Mirror Breaker and artifacts combo are open), and a blitzy spellslinger aggro.
https://cubecobra.com/cube/deck/62abca0188da1a0ff840beeb
Jund: This one’s not quite there. It’s almost good enough in lands, aggro, and good stuff. Notable for also being a good framework for Aluren and Oath of Druids.
https://cubecobra.com/cube/deck/62abcc6d88da1a0ff840c7ed
Naya: This one’s in the same boat as Jund, but instead of lands, it has Kiki-Jiki, Mirror Breaker.
https://cubecobra.com/cube/deck/62abce3e88da1a0ff840d72a

Mardu: Good at aggro, but specifically Young Pyromancer aggro. Also has a control option.
https://cubecobra.com/cube/deck/62abd59388da1a0ff8411ad0
Temur: Splendid Reclamation has a home here. Temur also has a spellslinger archetype. https://cubecobra.com/cube/deck/62abd16f88da1a0ff840fce6
Azban: Sure.
https://cubecobra.com/cube/deck/62abd41688da1a0ff8410e15
Jeskai: Absolutely silly. Whirlwind of Thought is kinda stupidly bonkers. And Hullbreacher and Archivist of Oghma are availible there. And Kiki-Jiki, Mirror Breaker. Jeez.
https://cubecobra.com/cube/deck/62abcfd288da1a0ff840ebe1
Sultai: if you want, lands exists. https://cubecobra.com/cube/deck/62abd70288da1a0ff8412693