Personally I don't like the look. But also, if they did that, Valve would have to re-do EVERYTHING. Not worth it, Plus it's not the effect they wanted.....
I really wish more games were made with cell shading and/or cartoonish styles. It makes games less serious and more casual.
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As fort he comparison
I think the outlining is too thick on the weapons; other than that, I like it more.
Ehh. I don't like it that much. I like TF2 as it is now. It would make it look at little more cartoonish. But your edit does like quite nice. I just wouldn't like to see it in game.
That's not exactly cell-shading though. That's just increasing the thickness of outlines on the player model. To be cell-shaded, the detail textures would need to be replaced with single-color textures.