I would take those troublesome things out and agree on a cool barn door. It needs some color and texture. Find a big weather-worn door, with the big black tracks. Then put the team logo as a big stencil on wall instead - or even place on ceiling for him to look at when he lies in bed.

I'd do french doors. The benefit is that you can then use the back of the door to hang things, like on one side you could have a pocket holder for shoes, the other side you could have hooks for robe, backpack, dirty clothes bag.

I'll just be the one to say it- you're tanking your home's value by taking out hardwood floors on the second floor. But sure, that's your call.

As for the closets, don't add a barn door whatever you do. It will dominate the room in a bad way. Paint it the same color as the wall so it blends in.

Be sure you lay the carpet before you decide on the door....the door may have to be made shorter. I have doors like yours in our basement rec room....they are always coming off the track at the top. I have sliders in our bedrooms on the top floor and they work best for me. If they come off the slider mechanism they are easy to get back on BUT I think a barn door for your son's room would be great. Second would be just a simple double door that hinges open (If you have room to open them). His color scheme sounds neat!

I would wait also until you got the furniture in the room. I would just update the knobs. Barn doors take up sooo much wall space, and are clunky looking. They belong only on a barn. I have to agree with you on the carpet. There is nothing warmer, cozy and luxurious feeling than a carpeted bedroom. Plus it adds sound proofing if the bedroom is on the second floor. The house I grew up in had hardwood in the bedrooms on the 2nd floor. All you heard was thump, thump, thump when you were on the 1st floor when someone was in the bedrooms above. Hardwood, though pretty makes a bedroom feel cold and hollow. Especially in winter. I also have several folding doors in my house and they never come off the track. I think if they are not installed or adjusted correctly they will.

I would absolutely use two doors. It's a boys bedroom and should be fun! It's not as if you can't change them back if you need to in the future.