Your shower is similar to the initial layout of mine, except I don't have a window.

To start with, I'd recommend something along the lines of this:

The shower supply valve (in red, or alternate location in orange) somewhere near the entrance so the water can be turned on without having to enter the shower. With thermostatic valves, most people set the water temp with one knob and for the most part never change it afterwards. The only knob they manipulate is the volume ON/OFF.

Towel bar in green. Mine is heated, a Runtal Omnipanel. Doesn't have to be heated. Doesn't even have to be in that location, you could install it on the wall to the left of the shower valve, or not install one at all. But in a large shower with two exterior walls and a window, if you're in a cold climate, the Runtal will warm the space and warm and dry your towels quite nicely. The Omnipanel qualifies more as a radiant room heater than just a towel warmer.

Shower head in blue. Your shower is easily large enough for multiple heads. Consider an auxiliary rain
head on the ceiling, or a second fixed or sliding bar-mounted head on
the wall. I'd feed the second head with its own supply valve. The 5-6" wall keeps the head off of the exterior wall, but if you wanted a head on the exterior wall there is a work-around. For the exterior wall, I'd run the plumbing from the shower supply valve vertically up the wall, then across the ceiling, and then back down the wall to the shower head. When the supply valve is turned off, the water will drain out of the pitched ceiling pipe and out of the shower wall pipe, so if your house lost heat in a freezing climate, frozen water-filled pipes in an exterior wall would not be an issue.

With the shower head(s) on the 5'-6" wall, they are spraying towards the window, but the dimensions of the window indicate to me it's a transom window that will be high on the wall.

If you go with a ceiling mounted rain head, consider putting it right over the floor drain, or skew it a bit towards the window wall so someone can be under the rain head while someone is using a wall head.

Purple is a moveable corner stool. Three legs so no wobble on the sloped tile floor. Put it where you want to sit, move it where you want as a shaving foot stool, etc. I will always vote for a moveable wood stool or bench over a tiled built-in seat. If using the rain head, you can pull the stool right under it and take a 60-second sit-and-soak before getting out of the shower.

Stoll can also be pulled over by the handheld to shave legs. You can buy an extra wall bracket for a handheld and mount it at knee or thigh height, whatever works. Sit on the stool and shave with the head low on the wall. An alternative is a small foot ledge or toe bracket that can be built into the wall to assist in leg shaving.

It's really what you want. Shower alone, shower together, share a showerhead, each with their own showerhead, etc. Two heads on the 5'-6" wall would accommodate two side-by-side bathers comfortably.

I do recommend one of the heads in the shower be a hand-held on a long hose. that way you can use that head to spray down the walls and floor of the shower when needed. Hand-held heads offer the same quality spray as their fixed-head counterparts.

Anyhow, it's a starting point for conversation.

Heres what i came up with

Not knowing how you'd use the shower (single person, more than one, etc), I'll point out that in your drawing, all three shower heads will have the same approximate water spot on the shower floor. Multiple bathers may be wanting to stand in the same floor space to be in the water spray.

Sometimes that's good.

Other times not so good.

I'll primarily be using the shower but my fiance may join me occasionally. One of the shower heads will feature a spray wand though and we could always adjust the shower head direction. Still not sure if i want a center drain or a linear drain. Guess it'll be based on what type of floor i end up going with.

If it were MY shower...I'd go with a frameless door and get a larger shower space out of the deal.

I'd go with Mongo's. I have a similar set up to this layout, but have shower heads on opposite walls. Very nice for 2 showering at the same time, but the side by side would have been better.

I'll vote for NOT building in a bench. Get the stool in wood. Tile or stone seats are just "weird" feeling on your cold / wet / naked butt. Sitting in a shower is actually kinda gross feeling (and my butt is the only one that has sat on my built in seat...). With a bench, especially teak, it won't feel as cold as tile and with slats it won't have water sitting on it.

I would tear out my bench in a heart beat and maybe put back a footrest for shaving legs. The flexibility and floorspace is far more useful than a bench.

I'm curious about the benches... Jannicone, would you like a tile bench better if it were heated?

I'm curious about the benches... Jannicone, would you like a tile bench better if it were heated?

Heated or not, I don't like the one I have in NY. I don't go into the shower to sit. If I want to sit, I'll take a bath.