OMG, a 4x4 shower is TINY!!! Our current shower is about 4x5 1/2, and we think it is small. House1 had a 4x7, which was adequate.
My dream shower (next house) is no enclosure at all, just an entirely tiled bathroom with a drain in the floor near the showerhead wall. I would have a tiled “seat” along the wall and a between-the-studs recessed niche for shampoo, etc. Something like this:
https://i.pinimg.com/736x/e3/19/ad/e319ad5814d08a454ffe5c2f1a3032a0.jpg
We rented a VRBO home with a very large door-less shower. To me it was cold and drafty.
The thing I like best about our frameless door is that it can open out into the room for safety or into the shower to save space (keeping the door open let’s the shower dry faster).
We have a similar door. I like to open it into the shower after showering. Very convenient.
We just remodeled our master bath and we went with a larger walk in so no door or curtain. Its an 8 x 5 and we love it. The back wall away from the shower head and the one side wall are only 6 feet tall and we also installed two LED recessed lights so plenty of light. Having now used it for a few months the water never get’s to the back wall so it allowed us to install the towel hooks on that back wall and also a place to hang a robe.
Probably larger than we needed. Didn’t seem like it was that big until during final inspection my wife, daughter, our contractor and myself were all standing in it and we still had room for more.
If I were going to tile a shower, I would use either large format porcelain tiles or quartz for easy cleaning. Yes for clear glass doors.