1. Move the walls towards bedroom (which is huge)If you think you won't miss the reduction in size I would go for it but I don't like the idea of the wall being so close to that window.
2. demolish the wall that parts sinks with the rest of the bathroom I have always like a big open bathroom but a very common idea now is to put in a water closet ( toilet in it's own room with a door).
[I]3. install triangle bathtub (jacucci like) I am not sure if it will fit
[/I] Another common idea and I like it.
4. put tiles and tops and elevate the top a little bit It always looks better if the tiles on the front of the counter top are not to skinny but then how much of a height are we talking here, it maybe better to raise the vanity depending on how high you want to go. Tile tops are thiker than regular counter tops so you may be alright.
Plese before taking down walls make sure there not load bearing because YOU NEVER KNOW.