We have a 5 x 3 enclosed steam shower, obscure glass doors, with a single low voltage LED light centered in the ceiling of the shower. The shower would be way too dark without the light. We don't have issues with shadows, possibly because of the white reflecting shower walls.

My master bath 2 sides glass shower has a light just outside shower & my guest bath 1 side glass 2 sliding doors shower also has light just outside shower. Both showers also have a window nearby.. The lights were specifically installed outside showers to provide more light to overall bathroom area when not in the shower. This plan has worked great.

ETA exhaust fans in both baths are on their own switches. Also, a reason given to us when we made our light placement decisions was that a light inside the shower - or over a bathtub, would need a different type cover which doesn't provide as much light. Something about electric code & water…. so, light outside is brighter than one inside the water space would be. My ceilings are 9' so no chance of trying to change light bulb while taking shower but code is there for a reason..

Here are more pics that didn't post.

Other bathroom with same type lights.

We have a very similar setup, with a light above the shower. We never use it!

I use my shower lights all the time. Mine are by dals. They are only as deep as the drywall and are self-contained and do not need blue electrical boxes behind them. If you can get the electrical wire to them, you can put them anywhere without regard to ceiling framing. I got them at Build.com for about $40 each. LEDs.

Shower is 62 x 37 inches.