I'm guessing it's a little smaller than you estimate, but hard to say without dimensions. Moving the toilet toward the door probably would help, but not necessarily enough to justify the expense. It's not an easy thing to do.

I am thinking to replace the current door with slide door, or move the sink to the other side and separate the shower from the rest with a glass panel

This is a “wet room”; the entire room is a shower. Moving the toilet and sink would be expensive because the plumbing must be moved. Perhaps a long, narrow sink would allow more room to use the toilet.

Seems something like this would work better. But you'd probably have to bump out the back wall to get the plumbing in. The ease of moving the toilet would depend on the subfloor. Is it wood or slab? To get it configured better you would need different wall mount toilet and vessel sink and all new tile and waterproofing. So it would basically be a gut job and serious expense resulting in still a tiny wet room bath.

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Couple more.

I like how nothing is stylized or dated, just pure wet room. I wouldn’t interrupt the waterproof floor of a wet room unless you are planning an entire new bathroom, it’s a giant shower stall that has happens to have a toilet & sink with floor drain in the middle. You might be able to take out the pedestal sink base (not connected to the waterproofing in the floor) and do a wall mount sink so at least the floor will appear continuous/less crowded. I remember bathrooms like this in Europe, you get in and out of there - no need for storage or towel racks or cosmetics or hair dryers, all that stuff was in the bedrooms where there was another sink provided for primping. Some of the wet rooms I remember had no sink, just toilet & shower (and some were much tinier than yours!) because sinks were in the rooms. It actually worked out great when sharing one bathroom with roommates..

Would it be possible change the door swing from in to out? that could open up some possibilities on moving the sink.