I was governed by the need to bathe a toddler easily as well as guest bathroom 8 years ago.
I am sure there are better solutions out there these days but this is still working (aside from the fact DD trashed the plug push up thing so we need to lift the plug up manually if anybody has a bath:
Double-ended steel bath (Bette)..so there is more of a flat area at both ends and the plug is in the middle, as was the water feed.
Hansgrohe Showerpipe - so the hand shower piece fits into a pipe that leads to an overhead shower (this makes it easier to push the shower screen right back out of the way.
Wall mounted 3 control wall panel with thermostatic valve and 2 way mixer (so top lever turns the shower on..middle controls temp with a limiter..bottom one leads to the bath). Mine was a Cifial. I am sure there are others these days
Folding shower screen that folds into and out away from the bath (so make sure you position the shower head high enough).
Bathstore (amongst others) do this curtain rail that has a small pane of glass as well, so you get the watertightness of a panel for showering without having a great bit of glass in the way when you have a bath (you just tuck the curtain up)