The unupped one is really underpowered and the upped one is really good.
The unupped one gives a card disadvantage, for one thing, so that would deter a lot of players from using it. If it doesn't work, you waste 3
and one card for nothing; if it works, you both draw a card and it still costs you one card, and I'm really having trouble imagining any deck that would benefit from this card.
The upped card, on the other hand, has the potential to draw a lot of cards, and thus even though it can cause card disadvantage, it's still well worth it, as you could gain a massive tempo advantage by getting to play the newly drawn cards first. In addition, if you play it when you have a small hand and your opponent has a bigger hand, and massive gamble triggers enough times, you might even gain a card advantage yourself. I could see this card working in many different types of decks to great effect, from monoentropy to rainbow to deckout. I think I would remove the clause about continuing to draw if your hand is full to balance it; if one player's hand fills, then the card effect stops.