I agree with emily. if you want leave connections and/or a little extra room for what you don't want, but feel you may need for resale. I think the tub is a pretty important item. wet room not at all, and shower is give or take. i would prefer a big shower and a tub for soaking in, but I have always had the combo. I remember my mom built during big wet bar craze, she did not care for one. had space built, capped off connections and use as a closet. Now it is 35 years later, everyone wants to buy and tear down. Darned if you do, darned if you don't. i agree, I would also really like the separate toilet, we are not share everything people.

Third vote for getting a professional involved, but i'll still offer my layman's suggestion given that you're just soliciting general ideas at this point. If it was my space, I'd switch the bathroom and the laundry room around, keeping just one of the walls currently enclosing the toilet. Its hard to estimate precise measurements from the drawing, so it may not be feasible, but here's what i mean

We have a 900x900 shower and it's plenty big enough. Neither of your proposed layouts looks that great, to be perfectly honest, sorry! In the first layout, you could improve it quite a lot by swapping the toilet and vanity (centre the toilet under the window on the bottom right of the picture if possible), and having the shower door on the other wall (beside the door). Then, you could have a towel rail on the wall beside the door (i.e. behind the door when it's open), which would be accessible from the shower but hidden when the door was open. An 800x1200 shower might be a good size for your space. You'd have to choose a toilet that doesn't protrude too far, plus a narrow vanity. With that layout, you could have a long but narrow wall-hung vanity, with a big mirror covering the wall between the windows, which would make the room feel bigger and would give a good amount of storage. Also, you may find this helpful: http://www.houseplanshelper.com/small-bathroom-floor-plans.html?utm_content=buffer4aa20&utm_medium=social&utm_source=facebook.com&utm_campaign=buffer

I love three in ones because if one bulb explodes, you've usually got a fair few backups before you have to completely fix the bulb (but that's just the laziness in me coming out). In my opinion, I don't think you need a demisting mirror because that's what the fan is for in the three in one.