We already had a walk in shower so I'm just going to repurpose the area as a fold out laundry station, but it'll mainly be my wife's makeup area.

I always hear people asserting you need a tub in every bathroom, like you we already had two tubs, don't know what a third jetted tub does other than exhaust the water heater even faster.

As far as the shower I used the Schluter system, worked really easy for a novice like me, although a bit tedious it's definitely worth it in the end.

Our shower was enclosed on 3 sides so I pulled down part of one of the walls and made it like a 3/4 height modesty wall with glass wrapping around to meet the door. Makes the shower feel much larger, helps with light, ventilation, etc.and did that without moving any plumbing or the drain. Not a big deal if you want to move plumbing but a lot faster if you elect not to. That changed the overall look of the bathroom quite a lot.

I definitely suggest adding a "cool" feature while you are at it which will make people forget there's no tub in there like a neat shower head or what I did, which is an animated LED shower light. You can run different programs or make your own or just run it as a straight light, dimmer feature, etc. Very expensive for a light but it's a feature, not just a utility