I'm surprised how much better that looks. I thought it would be an improvement but it's better than I imagined. Not sure if the mirror now ends up too high but it looks nice on the render.
Probably not worth too much further work until you are a bit further along. Still, do bear in mind trying to keep a single line going from the windowsill, through the second shelf on the nook*, through to the level of the nook in the shower and, bonus for points, to the level of the handle on the shower door
* You could adjust the lowest point of the nook to maintain spacing or switch to 3 shelves rather than 4.
Maybe. Not an area I feel knowledgable enough with to answer. Sure someone else can say more though.