Heya,
Those are heavily processed. Personally I don't care for it, because all I see those filters doing is slightly over-exposing to basically white out skin to make it smooth, and heavily saturates to pop color.
Also, don't shoot in TV mode here. Go Manual, or AV. You want to control aperture to be wide at all times, and unchanging. Use ISO to push the shutter speed to a fast enough value to avoid motion blur (1/100s is often enough, but maybe shoot closer to 1/200s or faster if possible, to avoid all blur and get the sharpest you can get, since your lens lacks IS, faster shutter speed compensates for this; heck, push it to 1/400s if you can, or faster. Again, faster is less blur and sharper image. You get exposure by pushing ISO higher, the 5D3 can handle the ISO just fine, so don't be afraid to push it).
But the base photos are being done with shallow depth of field. So generate that however you wish. With your 24-70, you can do that by opening the aperture up as wide as it goes (2.8 I assume). The closer you get to your model, distance wise, the more narrow the depth of field will get. So wide aperture plus close distance equates to a very thin depth of field. Meter on their face. Focus on eyes.
If you use the 24~35mm end of your lens, there is distortion in facial features. For portraits it's typical to work at 50~70mm on that lens, to avoid distortion of features (like noses getting big and bulbous). But that's not to say you can't use the 24mm end, for creative stuff. Just be aware of the distortion.
I would use the 50~70mm end, at F2.8, outside in the environment. Make sure there's nothing behind your model for a vast distance. This will help generate more blur combined with the wide aperture and close to subject distance. That's how you isolate the model from the environment.
1. Work on getting correctly exposed photographs with the properties you want, before you worry so much about getting plugins to automatically over-expose and smooth out skin for the `glam' look. Become a photographer before you become a painter.
2. Yes, see above. Don't use TV. Use Manual or AV. You want to control aperture always. TV doesn't let you control aperture. Use ISO, it's fine to pump it up, just get exposure correct and it won't matter. Nothing wrong with ISO 1600~3200 on that 5D3, so don't be afraid to go there. It goes higher than that. But you shouldn't need that much for portrait, just used it as an example.
Lighting. Lighting. Lighting. Those photos may or may not be all natural light, or a mix of ambient and supplemented fill from a speedlite, strobe, or whatever. But I'm betting there's lighting involved, it's too even for even natural light. I use portable wireless speedlites in small softboxes outside when I do portraits. I also do natural light if the sky is playing ball. Otherwise, I use a portable softbox (or umbrella) setup. Portraiture is all about lighting. If you slightly over-expose skin, with a speed lite from a softbox, you'll notice that it smooths the skin and gives that smooth angel look, without any processing at all.
Very best,
