Bathroom Design Reno Advice

Cloudburst

Friends, tilers, bathroom designers, lend me your ears! ... please? I would really appreciate some advice on my bathroom reno in design and practicality. I have to re-tile the main bathroom which has a shower and a long vanity on one side, and a bathtub at the far end.

My main motivation here is that the shower leaks so a re-tile has to be done at least in the shower. Then I thought, well, I may as well update the whole room. So while I am not throwing piles of cash at this project, I am always conscious when doing such projects of a design that will appeal (or maybe not put people off) if we decide to sell the house in a few years.

I have the 200x900 wood look floor tiles already. The wall tiles, if I go down this path, I have thought of a simple white matt rectangle 600x300.

Two methods of moving forward, just replace/update vanity, remove old tiles and re-tile. Or go a little different design at the same time.

The different design I've pondered is extending the square closed shower to a longer open one. Two main reasons, one as I don't like how the door to the shower clashes with the door to the bathroom. Secondly, I think a walk in shower looks nicer and is easier to get in and out of. But, what do I know! The cons are that the space is wasted on a shower where it could be put to better use in a larger vanity with more cupboard/storage space.

I'd like to change the bath tub but the height of the window restricts what I can place here and in all honesty, the tub is probably fine as it is.

1. So my first and main query is, what design would you do here? Open or closed shower? Same or different? It is restrictive in space, I know, but I'm totally open to suggestions whether it is agreeing with my design, a slight adjustment or a complete change. I just need some ideas to explore before committing.

2. Wall hung or floor mounted vanity? I've been suggested to go a wall hung but then the drain will be seen so not sure about that idea. I can't do anything about that drain position.

3a. A common question but I'll ask it anyway, should I completely tile the walls or leave bare as is?

3b. If tiling the wall, what to do with that cornice where the ceiling meets the wall? Remove, tile up and then replace with new cornice?

4. Any other issues to be aware of that you can see.

I have a tiler ready and, if need be, a plasterer.

Some images of existing and also of new design idea:
imgur.com/a/hmwXV4L

Cheers