My math may be wrong, since I didn't hand count each weapon, and counting skins may be off (I assumed there was 15 per a pack, one new pack had 12 skins and the other had 13, plus the dragon skin)
Now, the introduction of War Paint stated any weapon can be painted, including the pyro's new primary ONLY, that's roughly 127 weapons total
There's roughly 146 weapon skins, counting elite and assassin grade, and considering they said they'd remake all skins I'm including those.
There's 5 wears per skin
There's 2 skins depending on if it's strange or not (that means the stat clock counts as a separate skin)
There's 2 skins depending on whether it's festive or not.
There's 4 unusual effects, and apparent the war paints can apply those
So saying every weapon can be skinned, and weapon qualities are counted
The way to find the entirety of every new skin+weapon added to the game should be
2×2×4×5×146×127
And that's roughly 1,483,360
This truly is a massive update on skins alone