I am trying to figure mine out too. Lighting will affect how the paint color looks in your house. One color can look great in one person's house, terrible in another. Your local paint store may have someone who can do a consult for a low charge. I am not an interior decorator, but in looking at the photos, it looks to me like your rooms could look better with a little more color somewhere...in the walls or art, or accents or flowers....I need to do all this too!

don't know what the budget is or what your DIY skills are.

Look on Pinterest for "updating bathroom on a budget" or "how to do a cheap bathroom makeover". you should get a lot of ideas w/links to blogs and plenty of how to's.

Are you in Canada? you might look on Kijiji for remnants of granite countertops or look for bathroom vanities, floor tile, fixtures, etc. I find lots of things on Craigslist. People buy too much tile or wood flooring and try to unload the rest of it. you could find a remnant stone piece, have it cut for a new sink and use it for your vanity top. You could paint the vanity and get new hardware. (Google 'how to paint bathroom vanity' for you tube videos and other links)

your bathroom w/the red towel looks updated, I would get a bright white, glossy paint and redo the baseboards and trim. Then I'd find a new wall color and do the walls. Remove the heavy, bulky trim from around the window and replace with something thinner. Miter the corners so you don't have those square corner pieces. (like you have on the window in the first pic) Remove those mini blinds and replace with a roman blind or shade of some type. Do this on all of the windows. Do you really need blinds on the windows at all?

your bathrooms are basically fine. You said it's blah! just changing some wall decor isn't going to do much. Decide what look you want first, and go from there.