If you want to make the most of the space you have, have a luxury bathroom suite and don’t mind paying a little more than the off the shelf prices then a bespoke fitted bathroom is a way to go. There are a number of companies out there that offer bespoke bathrooms that are made to measure and they often can accommodate more than you thought possible within the space you have.
Most of these companies will have showrooms where you can go and look at examples of the types of suites and fixtures/fittings they have. Some companies make the furniture in-house and others will ship the order out to a third party but will be responsible for the order through to fitting.
If you have an idea of what you want then why not go and meet up with one of their designers who can often create a 3D visual of the bathroom to allow you to picture exactly how it will look. Working with awkward spaces is usually not a problem for bespoke bathroom fitters and because the bathroom is made to fit your bathroom measurements it will often look better than buying off the shelf and trying to adapt it.