So I think I found what's the problem. It's NOT beauty. There are three factors that contribute to weird photos.
I think FIRST of all it's a problem of contrast and temperature. It's like if these guys at Samsung thought that reducing default output contrast would add a feeling of beauty, and this might be the case for some people, maybe for people with strong outlines and rough skin. I in contrast am a bit pale with smooth skin and outlines. So that's why reducing contrast might make my features disappear making me look sick/cartooned. The image information is there though, it's only that with low contrast you can't see it (the human eye can't distinguish two light intensities that are less than 5% apart and there is variability among the population). The simple resolution for this is increasing the contrast/temperature in the output photo. I don't know if this can be made a default option. This is independet of the camera you are using, front or rear.
SECOND, the strong perspective which is, for what I know, a characteristic of the small lens diamenter, which you can't change, so you can't do much about it (there are some apps though that might correct this in post processing). This is why selfies distort the face. I think you will have this defect in all smartphones. Smartphone lenses are rather small compared to a reflex lens and I think you can't get control over perspective in s6.
THIRD, low/inhouse lightning. Light the flash and you'll see the difference(nice, high resolution and crisp images) whilst in low lightining condition the amount of detail will be very low. It's a matter of illumination and quantity of light that enters the objective.
If you sum these three effects you will have terribly looking photos, this might be true for some people, maybe depending on their personal features and on what they feel is nice and what is not. As stated before, also the options of the s6 screen might be at play.
So my suggestions for those experiencing this problem are:
1-For photos shoot outdoor(sunlight), increase the contrast/temperature on post processing. Find a way - I will search how to do that - to make it a default setting.
2-For indoor shootings, avoid using the selfie mode unless you have a strong light source pointing at you (you can't use flash in seflie mode). For the normal mode (front camera i guess?) use the flash. Either way, increase contrast and/or temperature. Even in selfie mode, playing with these two parameters will reduce drastically the plastinated effect we are talking about.
3-Additionally, you might want to avoid the perspective issue for the best photos, then avoid selfie and use timed photoshoots placing yourself not too close to the objective.
These are workarounds to this disappointing preset, but your photos will look far more normal now.