Bathroom planning - is the space sufficient?

We also have 70 cm clearance at the toilet and shower,

It’s not about the clearance, but about the basic space. Normally, a clearance for the shower is planned with 60/70 cm, but then the shower has an overall length of 160/170 cm. A shower partition has to be installed here anyway, so the T is unnecessary. Before worrying about Ts and Ls just because you want them, whether useful or not, I would rather consider that a washbasin benefits from daylight and you shouldn’t place yourself between the mirror and the window, because additional mirror lighting creates shadows. Also, a toilet could benefit from a window where it receives natural light.

The space for the shower and toilet is sufficient, although not generous. Water will splash out of the shower area; you just have to push it back in with a squeegee. Our shower area is 1.45 x 1.35 and has a tiled seat. When using the rain shower, the water reaches about 30 cm beyond the partition wall. To avoid wasting too much width for the toilet on the other side, we integrated a shelf behind the T, before the toilet. Shower without a shower tray, but with tiles sloping slightly. The drain set as a wall drain under the partition wall is very elegant. The flush tank is also integrated into the partition wall. We built the wall between the shower and toilet about 1.20 m high and then placed a glass panel on the middle of the partition wall. This creates a shelf on both sides and gives a better sense of space. Do not extend the T all the way to the ceiling; leave some space at the top. This also creates more space. A height of 2.2 m is completely sufficient for the "T". Swapping toilet and shower is sensible. What proves very practical are two dimmable LED spots on the right and left below the toilet (set to amber color in our case). This way, you can find your way at night without needing unpleasantly bright light.

Our shower area is 1.45 x 1.35 and has a tiled seat. The water when using the rain shower extends about 30cm beyond the partition wall

And here from the showerhead to the end of the wall is only 40cm, I think you don't see the problem. If the showerhead also protrudes into the room because it stands 20cm away from the wall, the water will definitely end up in the room.

If the toilet is really to remain as it is, I would also swap the WC and shower if possible due to the drainpipes.

With the shower, you then know that you might have to wipe. Not everyone does! But in front of the toilet, which you might use more often, it is then dry.

And here it is only 40cm from the showerhead to the end of the wall, I think you don’t see the problem. If the showerhead also protrudes into the room because it stands 20cm away from the wall, the water will definitely end up in the room.

Of course water will end up in the room there. That’s why I described that with a clearly "T" there is still water next to the sink. When choosing and placing the shower fitting, you have to be especially clever, because there is still some "dryness" to be gained there. For the shower, there is not only a symmetrical arrangement on the partition wall as a location – as is generally usual.

2.82 m depth for the T in the raw construction dimensions would be too little for me. Roughly calculated, a shower with raw construction dimensions 90*90 and depending on the partition wall 12mm + 15mm facing about 1.6*90 for the WC. That all works. But if I'm building new, I don't want to build the whole bathroom on the basis of "it still works." Without having thought of an alternative, I would just erase the T and look at what alternatives there are, beyond the T.