64 is the better of the two, with Legacy's additions, other than save points in Duel Tower, being rather uniformly terrible. Hi-res mode is barely playable, and the game's full of horribly balanced abilities, like throwing multiple subweapons at once, or giving one character a hitscan, infinite range gun with a skippable reload animation.
The new levels are a mixed bag, but it's a mixed bag of different kinds of awful. Foggy Lake is dull, the new Forest of Silence lacks the sense of scale the old one had, and Cornell's quest redefines the concept of 'filler;' whether it's being forced to climb one of the towers in Castle Wall twice, or the unbearably boring run through Villa's garden maze backwards with no music and nothing chasing you [or the unbearably boring escort mission that follows] the majority is just focused on time-wasting and padding. Art Tower is the worst since the padding is spent listening to ticking sounds on the pause menu or falling off an impossibly narrow rope, but all the re-imagined levels are pretty poor: Tower of Sorcery has lost most of its graphical detail [the sparkles in the background and floating bubbles are AWOL], Science goes from hilariously difficult to hilariously easy, and so on. The game closes on two cheap, stupid bossfights, the last being particularly heinous in that regard.
Henry is worse, especially as a replacement for Coller. He's Reinhardt's character model with what appears to be an axe armour's head thrown on the top, given a ludicrously prefunctory quest that really adds nothing to the storyline and no enemies designed to take his unique abilities into account.