My fiance and I really like smooth, but we were advised that no matter what a great job the painter/contractor does, those imperfections will show.  

Many older houses have imperfect sub-floor and installing too thick laminate will be just wrong decision.

If the switch is white you can just spray paint them.It depends on what kind of rental you have with what they expect.We have small old water stains from previous leaks on the ceiling when tenant moves out.I buy a spray can of Kilz for 5 bucks and usually last about for 2 of my apartment units hitting spots.You can't tell afterwords with the ceiling and it looks great.It's cheaper than scraping popcorn and trying to match or scraping the whole ceiling and a flat ceiling because it is old showing all imperfections if you just scrape and paint it.On the light switches I agree it works to replace them all but in older apartment buildings I try not to do that because what I have found is the wiring in behind is cut short or has too much excess crammed in.So if the wiring was all clean and the right slack from out of the box it would be easy to replace.I have found that some go smoothly and the others are a bit of a pain to change out making adjustments.The Kilz for the ceiling I only do that on non-active leaks where the drywall still has integrity to it and is not sagging.If it is sagging I cut out and put a patch in and then popcorn over it after priming to stick.All my tenants want is a nice,clean place to live.If you have a high end tenants paying premium bucks then finish level and what the tenant expects will change.In mine replacing everything will only net me maybe another 30 bucks a month in rent and the thousands spent will take 5 to 8 years to recover if everything goes perfectly with each unit.

Got a hustle for this.As a DIY landlord and renovator, I do my house painting myself, in older rental houses that don't rent for a lot of money, on plaster walls that are decidedly imperfect.

I also found that sometimes the look that you are going for (texture and no wall imperfections) is easier obtained by replacing all of the sheetrock in rooms that contain plaster which needs patching.

Flat tends to get dirty and shows imperfections rather easily; or am I confusing that with something else?

Staging helps buyers envision living in the house, especially a small or odd floor plan and a furnished house camouflages imperfections.

Its not perfect but its an old house with several far more obvious imperfections.

One little irrelevant paperwork imperfection might cost you 0.25% to rate in Fannie world, but it's going to cost you - easily - 2% to rate in portfolio world.

Chad Beeman explains his strategy in scaling, and how to navigate pulling all of your money out of an imperfect BRRRR.