In my opinion, part of the "nice" answer is going to boil down to your color transforms. Porta800CD is cool but it doesnt resolve the 32 bit linear to 8/16 bit problem of blown out colors and over-saturated light sources and highlights. Really, it is very hard to fix this in post on its own. Once ACES and filmic view transforms became standard some years ago that really fixed a LOT of that problem and helps with the "niceness." Going to the point of your material it's self, you probably need to change the universal material to diffuse. That is what gives the SSS plastic look. Technically then your transmission becomes translucency and then if you want to add a random walk volume you could.