In the early days, we'd paint the whole "room" one color, but with time, we realized that a mix of different colors allowed us to up our game and make more dynamic and interesting mechanical suites for different settings
Battle of Wits Although it's always been a meme, there were people playing Modern leagues time ago with Battle of Wits decks
Once banned in Standard, this marvelous artifact generates energy faster than most other cards, and has one of the strongest outputs, putting creatures directly into play from your library
You can build around this card with energy, +1/+1 counters, loyalty counters, spacecraft, and so much more
Both Yorion and Brago serve as great flicker deck Commanders, so it really comes down to a matter of preference
For more words on Magic, check out the powerful new planeswalker from MTG Duskmourn