Hello,
I would definitely prefer option 1 as well - No. 2 is really critical because of the sloping roof and would probably also lead to the bathroom flooding if no door were installed.
Our shower is 2.4 m long and has a side entrance with a width of one meter.
We have installed a towel rack on the rear end wall where the towels actually stay dry.
Showering together is very comfortable for us with an interior width of 1.10 m.
The walls of our shower go up to the ceiling - lower walls with a "ventilation gap" to the ceiling would not have worked for us because I am 1.90 m tall and the shower head we installed should hang at least 30 cm above the head in order to function properly.
The exhaust of our controlled residential ventilation system is located on the rear end wall - however, not facing the shower but towards the toilet. We still do not have any moisture problems.
One more recommendation from me: In the front area, I would have a niche made in one of the side walls - shower gel, shampoo, etc. are then well stored there. In our case, this niche is as large as one of our wall tiles and tiled all around (also on top). The floor of the niche has a very slight slope towards the shower so that splashed water drains off, but nothing else falls out.
Regards,
Dirk