You could consider ripping out the shower base and tiling the existing 830 wide and extend that all the way to the existing bathroom wall at the opposite end of the bathroom wall. It would create one wall at an angle but with a seamless glass shower screen and a new tiled floor and walls it wouldn't look out of place. That would allow far better body manoeuvring in the shower.

We did a kitchen in a holiday house approx 13yrs ago, with a Wenge laminate runnng across the panel for the kitchen and bench top plus a Kahki colour for tall cabinets that housed the fridge and laundry. The floor tiles were like concrete and island bench had a white bench top, this was for use indoors and on the outside deck

custom made vanity and wall cabinets should only be needed if you have awkward sizes as an off the shelf cabinet allows you to see and touch the product and is often much more economical than custom made ...unless you need to keep some special supplies (eg 24 pack of toilet rolls?) i suggest that a base cabinet need only be 450-500 deep which is plenty for folded towels and drawers and the in wall cabinet about 150mm deep (including most of the cabinet inside the wall and only a small frame for doors and mirrors projecting out) but the in wall cabinet may depend on existing wall studs and electrical wiring so think about what you would put inside the cabinets and only have enough inside cabinet space for those items (maximum toilet roll or fat shampoo bottle about 120mm...in small bathrooms the extra floor space makes drying and dresssing much more comfortable and by rotating the shower in the family bathroom there would be less wet floor in the walkway and if the vanity in the ensuite is away from the corner you can allow space for a handtowel and/or a very convenient space to hang a hair dryer ...

Before choosing any surface, do the finger test, unless you are house clean slave. The finger test is see what marks show with a slightly greasy(hand lotion) fingers. Most blacks show finger marks big time. Same with counter tops. Best test is scatter with bread crumbs, if that disturbs you forget it, otherwise you will be kitchen cleaning all day. The same goes for concealed handles, they quickly get full of crusted much and chip easy. A working kitchen needs to be practical, easy to clean and totally family proof.