You already did the hard work of building a deck capable of producing the rainbow, so why not double up on your spells with the cascade granted by Maelstrom NexusMaelstrom Nexus
Remember these rankings are for the entirety of their Standard life, and the individual cards may see a fluctuation of value during that time
Phabine, Boss's Confidant is a solid Naya commander for six mana that utilizes parley to bolster your own offense
That goes double for a Niv-Mizzet, VisionaryNiv-Mizzet, Visionary deck, where the more efficient burn spell you could be playing instead for one mana will draw you more cards to get more burn spells and keep the whole cycle going
While skipping one-drops is doable, especially in slower decks, not being able to play three-drops as well means that playing Gyruda, Doom of Depths as your companion essentially means that you're guaranteeing you'll cast a maximum of four mana worth of spells (two two-drops) across the first three turns of the game, which is certainly too slow for older formats like Modern and Pioneer, and likely too slow for Standard as well
The curses attached to a player go to the graveyard when the enchanted player dies