These are all great points, and I must admit I didn't even think about these things when I made this card lol.
But, I'd think that these things are up to the developers to decide based on what makes sense in terms of coding and systems. Personally, I don't think this card should affect/change the max number of cards a user is allowed to hold at the end of his turn because that's not this card's effect.
At the same time, maybe we can just create a permanent card that allows users to hold more cards and make it a combo card with Time Avatar. Maybe?