First, here are the pics: This isn't anything that serious. The use of a dremel tool with a grout removal kit, or with a 1" diamond wheel will take care of the grout joint between the broken tile and the tiles that are still good. After that, the tiles shouldn't be too difficult to remove with a hammer and 5 in 1 painters tool. As for what to put back, if this is a temporary fix, pick up about a dozen pieces of standard white either Dal or American Olean 4 1/4's as well as a dozen pieces of 4 1/4" bullnose to match (trim number S4449), and some thinset (NOT mastic or premixed thinset in a pail-- the powdered thinset that has to be mixed with water), and some white unsanded grout (again, not premixed), and that should be all you need.

I wouldn't do anything behind the tub, as much as I love art in its different forms etc. I like visual proportions as they are now-chandelier, window, tub with its faucet. I wouldn't want to interfere with it too much. Your window is your art...in a sense one really looks at it. I'd do someting both beautiful and very useful next to the tub-like a side table where one keep soaps/brushes (yeah..they should look good))..maybe a cool thing-y for towels (it's very hard, or else I found it to be real hard, to find something cool and free standing and narrow enough, especially new..new costs some abnormal amount of money. I personally decided to manage without..)..plants are always a good idea, to me at least One can do a shelf I suppose..but it won't stay empty, right? If you really prefer to, I'd go for smth not full length..assymetrical..I wouldn't want to repeat the window lines.

Well, to be optimistic, it's working for what you need right now...I do have the feeling that the toilet clearance is not to code tho... My guess is that the current tub/shower combo has some kind of damage to the outer wall (not the part that holds the water) and the previous owners got it cheaply and covered it up. In your position, my future plans would be to demo just the front. The amount of damage that was existing or I created with the demo would be the deciding factor of what to do with it. Some cosmetic damage can be creatively covered (NOT like what they did...). If that's not possible, I would replace the whole thing. Basically one step at a time. Right now, though I would remove the grout. You're the only one who knows exactly how much gets wet (whether the wall grout or just the deck grout). If it's just the deck, I would try to crack that section in the corner so I can remove the rest...maybe a flathead screwdriver and a gentle tap with a hammer? Then caulk.

You wait until you can replace the tile.. Actually, you wait until you can someday RE DO the bath, give yourself a larger shower, and for all we know a better layout in total. If you MUST? It's your money and wasted unless you address all the tile , When you think about that? Then read the first thing I said.. Sorry. Start a piggy bank. Feeling brave? Draw and measure the bath , add all dimensions, windows, entry, doors etc. Post pics from more angles. You'll get more advice.