I think you're underestimating the severity of this drawback. Especially early in the game, skipping one's draw step is some pretty harsh card disadvantage. Generating one mana of any colour isn't so good for one's tempo that this tradeoff is even. What might be an interesting rework of this would be something like this:
: Until end of turn, if you would draw a card, add one mana of any color to your mana pool instead.I'm pretty sure that this isn't particularly good either, but I think it's a more interesting take on the idea, if nothing else.