How can I change these boring doors?

Use oil based enamel for brass. Hopefully you'll like them better. They are very expensive doors and very desirable.

If possible remove the doors. Sand and clean with degreaser. Mask off the mirrored areas with painters tape and newspapers. Rusteolum makes a good primer and paint in a spray can. Light coats so it doesn't run.

Your bathroom reminds me of a Hotel I stayed at during a Journeyman project in NYC. I yet have flashbacks and nightmares about Cold Water from a showerhead. Ever I stay in a ☆☆ Hotel on Broadway again in Octoburrr I am taking my own Battery Operated Heated Showerhead, that's for sure. Now, to work. As far as Barn door hardware, you can find that at Lowe's Or Home Depot or Amazon. You don't need to buy the doors, just attach the hooks to the mirrored door, install the Bar and hoist up the mirrors on the hardware. You wouldn't be the first. Many ritzy places have that sort of layout in the Master Bath. Now allow me to give you my counsel: You do need to get rid of that carpet. It does absolutely nothing for the room except collect sock fuzz. Forgive me I'm Honest. Don't tell me it keeps the floor warm. Carpet is not insulation anymore. If you want warm toes put your socks on a radiator. That door on the Shower looks really fun to open for persons who like a challenge too. Have you ever gotten out of the shower to get all sweaty w8th an attempt to shut that shower door and then decide to get back in the shower? Looks like somebody did. ONCE. The shower door needs to be realigned and sprayed with WD40 to keep the brass from bending worst. WD40 like any oil or wax is a waterproofing agent. Brass is like that, very flimsy. To avoid painting brass which sure as shootin' will make the door stickier on humid days more than it already is when you need a shower most, I'd recommend a Tub & Tile Repair Kit while you are at Home Depot getting the Barn Door Hardware. This you can do to the brass to rid yourself of any idea that you should paint brass. Especially that Brass. That brass is ready for scrap. Save your money and buy New this time. Always remember buying yourself something is not a bad thing to do. Buying something that stays aligned by wheels and doesn't scrape and screech every time you open it is a start. Trust me on this: You will be happy you did. That blue flooring linoleum is nice... for a basement with bleu cheese colored paint on the walls. You don't need to tear it out, instead, offer it as Christmas gifts, possibly in frames and someone will take it. Naaah just kidding. Get like 5 boxes of Clearance peel and stick tile of a more neutral color like: marbled, white or gray or yellow. I recommend this because: it is certainly not 1930s Sacramento. Gray rarely belongs on the walls more than on the Furniture, Woodwork or Floors. Wall colors influence and enhance moods. Floor and woodwork colors enhance the wall. You got a Cloudy Gray day every day in the place where you should go to get bright and Sunny. In fact when I look at the color schemes, It reminds me of a Hollywood Special Effect of a rotating room on a crank. It looks like Harry Potter had a bad day and put your floor colors on the walls and your wall colors on the floors, to match the grout. Unless you plan to sponge paint all the woodwork gray, You really need that Tub & Tile Repair Kit: that gray grout has to go. Those hanging hooks with clothes on them gotta go too. They might block the doorknob. They definitely will bear weight on the door hinges. The doorknobs and those beautiful wooden doors are the only parts of the bathroom I like and wouldn't change atall. Why hide the best part of the Bathroom behind Robes? As far as Color Recommendations? I'd go Heinz Mustard Yellow or Sunshine Yellow on this one. You looked at cloudy gray for long enough. It is time to change the entire mood from dusty gray to Sunny. Go with some sorta Yellow Marblesque on the Floor Tile to match the Shiny Disposition. Get yourself Yellow Towels. Heck while you are at it, get Checkered Yellow Curtains too! You will be suprised at how much this improves your outlook.

RustOleum to paint the brass. Scuff with fine steel wool, wipe, then spray paint.

Overwhelming is my only thought to the first online response. Scrooge is alive and well. Being optimistic, life can be breathed economically into your doors. Consider painting your door trim in one of the beautiful rustic paint colors. Next go to several big box stores and in the rear you will find lots of wood pallets. Measure out your dimensions and collect your wood pallets and take home and disassemble them. Remove your closet doors one at a time to work on. Layout your pallet wood pattern on the glass door until you are happy. Either stain or paint your pallet slats and attach to your doors with (glue, etc) for a very chic, rustic look. You might consider a light glaze or stain over your pallet slat finish. Remember! Double check your measurements and use a level. It will be beautiful, chic, and rustic. Rehang your doors. Patience is your best friend. Slow and steady brings the best results. Merry Christmas!!!🎄

Paint the frames as stated above. You can also paint glass/mirrors. Use color or colors to match the paint or design you are going with. Use an acrylic enamel for glass.

An example...... you can do 3 different colors...... blue on top, lighter blue in middle and same blue as on top or opt for a darker blue. Just be sure to keep in the same blue wheel. I coat of matte poly will help keep scratches from occurring.

So many options for paint!!

Sand & spray paint on frames(do necessary prep),contact paper( comes in many colors,styles on mirrors) you can easily remove to change; you could use these as barn doors( add wood contact paper to cut down weight) just attach hardware and track. Be careful adding more weight(peel-n-stick tiles) to doors the tracks may not hold it