We also have a 70 cm passage between the WC and the shower, which is really completely sufficient. Back then, we also considered which side the WC and shower should be on and were able to switch without any problems because all the pipes converge at the back. I would also go for the L-solution to give the shower more length; for that, I would make it only 1 m instead of 114 cm, then you gain space between the sink and the bathtub. And I would switch them if the view of the WC from the bathtub bothers you.