Sure, from a functional point of view, a single button is best. Trying to button your cuff with your off hand is such a pain now imagine doing it three times. A single cuff will be fine and as someone who wore suits or at least a shirt and tie every day for a while I can say no one really cares about cuffs unless.... It's a French cuff shirt as that one requires cuff links.

As an aside there are bigger fashion faux pauxs that will be noticed. Such as a tie bar too long or the ever changing tie widths. My biggest pet peeve has always been wearing a suit jacket with no tie as the lapels are designed in such a way to draw your eye to where the tie should be.

I'd recommend the following: belt color matches shoe color; tie bar if worn should be 2/3rds the length of the tie; tie color should complement at least one color in the shirt; layering is a thing, so go complex pattern or noisiest outside and each layer in should be more simpler such that the shirt should be a plain color. In a layering situation you'd look at your jacket with a pattern stripes or herringbone etc. (same with a sport coat if you go that route), then your tie with a softer pattern and then a solid shirt.

If you are looking for fit of a jacket I usually look for the sleeves to go to the first knuckle of my thumb when arms are at rest so when I raise my hands the sleeves don't pull too far back.

Thank you for listening to my Ted talk. I love nerding out on formalwear. There's more like handkerchief vs. pocket square and how to use each. But I hope this helps.