Hmm... it's interesting that both have a 30-damage and 60-damage attack. I prefer the Lv. 44 version, but either is reasonable.
I like the Lv. 44's first attack, because a 1-Energy for 30 damage plus an Agility effect is very efficient. Although Glaceon "should" have 2 Energy attached when it has evolved, it won't always be that way! I would rather have a potential protection effect than a weak additional damage to the Bench. Thus, the Lv. 44 version has the edge here.
As for the second attack, the Lv. 44 version has the slight advantage here. Swift (actually, Brick Break) effects are nice, and for the Lv. 46 version, a flippy Sleep attack is essentially just the damage, since there's a 75% chance that the Defending Pokemon will be able to attack during the next turn. So it's basically the same attack on each card, but the Lv. 46 version can't get around Resistance or Agility.
Overall, although the Lv. 44 version has 10 less HP, its attacks are much better.