Impressions I've got from my first 16 hours of play

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Sounds - really can't fault them, I would hope that the hl2 sounds could be changed, but other than that, its all good.
Graphics - If this is a beta how are they going to make it look better? Its beautiful, little tiny details on each turret, gun, and player model helps to give this 'beta' a feel of richness.
Mechanics - The classes are all fun, if you feel like popping heads or just holding down the trigger to make a wall of bullets, its all there, plus the spy? Genius! Needs full servers to counter the scout rush, otherwise its constant rape, but at the moment they are full, even as I write this, after playing through the night, only once did it drop to 3 a side, that was about 4-4.30. The humour, the weapons, the flaws in each class, it's well balanced and leads to a high paced full of lulz game.
Things I think need tweaking -
Turrets, I think they need to be 2 things, tougher, and a lots less lethal. Enough of an annoyance that they partly block a route, demanding fresh tactics is good, but not so that you run past one thats fully upgraded and jump and by the time you hit the ground it's in bits.
Demomen, not so many people play these, but the one who do, and often, can hold back an entire team, maybe a bit less power on the grenade's, but unless everyone starts playing these exclusively, they wouldn't need nerfing.
Rockets need a bit more blast radius, the damage is fine, just seems to be a small and arbitrary circle o' death that the explosion creates.
Bit more long range accuracy on the heavy, sasha will shred anything close, no mistake, unless the player truly sucks. But even at medium range, the gun is mostly making holes in the pretty map textures, not players, plus the backup weapon of the shotty, thats another short range killer, but useless at longer ranges, this, coupled with the complete lack of speed is too much of a flaw in the heavy.
Final note, this game is teh fucking whin. Those tweaks up there are me being picky. Even when I die when I'm sure I should have lived, I get raged, then see something like "This is a bit of you!" and "This is your pancreas!" on the screen, you can't stay angry at that.
Also, falling asleep on the keyboard after being awake from 7.30am on the 17th to 2pm on the 18th, waking up and starting to play again, thats how fun this is, I need sleep now, but I don't want it, I want more teef.