Best Of

First of all, it is a nice sized apartment with floors and walls in great shape. You did good finding this space! A couple of things I would suggest 1. Turn your dining table so that the short side faces that odd opening leading to the kitchen. 2. I would balance that too small opening with matching posters the width and height on each side in a frame the same color as the molding with some black in the posters 3. Two rugs or carpets in a stripe or linear to pattern to ground the dining table and the couch 4. You need additional storage, maybe a simple plywood console table with L-brackets legs or inexpensive bracket legs and baskets underneath to hold blankets and stuff 5. I might move the sofa out to divide the room into two spaces with a rug under the table and one in front of the sofa to divide the space and make it cozier. I might move the TV console or just angle the TV 5. I would purchase enough IKEA paper shades and stick on hooks to create privacy but not block light on the window ( shades are $2.99 each) 6. A square of a bright colored fabric-tablecloth(your accent colors) on an angle on the dining table with a centerpiece bowl or vase 7. The other earlier suggestion on the alcove thingie by the window a hook for your bike

Free standing tubs look great, but are a pain to clean around and behind. Been there, never again. There is a reason all those cute cast iron tubs got boxed in during the 1930s and were gone by the 1940s.

Plus supplementing the wall tile if you go with the freestanding will be expensive, especially if the tiles are not exactly the same thickness.
Do you have a separate shower stall? If not, adding a shower to your tub, and enclosing the whole area allows you to use a different , coordinating tile right up to the ceiling.
The floor tile is also a problem. But you could choose a coordinating tile and make a rug around the new tub, in plain black, grey, or white. Perhaps with a smaller (one inch) tile as an edging.
Because there is so much missing tile to add, and so much to remove and replace, this would be a good time to replace the entire floor and wall tile. (In my opinion the faux barnwood wall and the arabesque floor do not coordinate, but YMMV.