Braking action "medium" shouldn't be too much of a concern for you, unless you have landed long and/or fast, on a critical length runway.
The use of auto brakes (at a low-med selection, rather than a higher setting), in conjunction with thrust reverse should be sufficient, and you won't notice a great deal of difference from "good" b/a.
Landing flap selected to give you the min. touchdown speed.
Aircraft manufacturers make adjustments to the max x/wind component, depending on braking action (Good, Medium, Poor), and/or the type of contamination - wet, water, slush, ice, snow -so that "significant crosswinds" are not a factor (for those of us who do follow the O.M.!)
My recommendation is NOT to go playing the reversers like piano keys - from max back to idle, back to max - as you're courting the possibility of encountering an assymetric (unequal) thrust situation.
By not using ANY reverse thrust (as you appear to be inclined to do), the engines will still be producing forward thrust during the landing roll, thereby increasing your landing distance - not desirable.
At least "crack" idle reverse.