They have actually already answered the question yourself. In reality, bathroom and bedroom as fire and ice. The bath should be the warmest room, the bedroom the coldest. In the bathroom is a lot of humidity and noise instead, the bedroom should have a constant normal humidity and shielded from the noise as possible. Your request resulted, as so many requests, from what you have seen in brochures and lifestyle magazines. Please keep in mind: PROSPECTUS ARE SITUATIONS never used!

Of course, everything looks great. But when will the sleeping partner and the other partner a shower at the same time (because he comes home very late, for example) it's past with the luxuries and the bare trouble starts.
Through a transparent partition, the sound problem could be solved to some extent (please note that sliding doors offer NO SOUND). However, this may not prevent the transparent wall, the light is. Besides taking a shower in the dark ...

It will be left to you nothing more than to be agreed with yourself, how much is worth to you this open space feel of any impairments. If you can agree with the other Badbenützern fact that only bathed / being showered when no one sleeps in the bedroom if you can sleep with increased humidity and higher room temperature, when you take the privacy that you would normally have in the Badbenützung can safely give up (teeth cleaning, manicures, pedicures, shaving, etc., etc. - virtually everything in a shop window ...?) then you can combine these two rooms.
For example, you most likely probably the single as a chance to achieve something. However, one must then remain single ...

Otherwise not. An intermediate solution gibts not. Even partial separations or glass walls may sound, heat, and humidity at best slow down but not stop it.

Moreover, your bathroom is actually not so small. With 2.8 x 2.8 meters, you are already above average. Look in the Baths database look at what you can make of it all ...
And a bedroom really does not have to be big - on the contrary. A small room creates a much more pleasant atmosphere, IF it is kept free of boxes, chests and other storage furniture. That most of the bedrooms seem too small, is because of the monstrous internals, by which they are disfigured. Fixtures that were necessary due to faulty planning of the apartment or house because it was forgotten on the closet ...

How does it look like for you with the room layout itself? If you can remove the partition between the bathroom and bedroom, they can also be set differently. Perhaps it could even be a better solution for both rooms without finding them together.