If the bar is decked, then it can only go down.  So the only question here is how far up do you want to be able to go if you set it float.  Most guitar techs (& websites covering the info) will tell you to set it an 1/8th of an inch.  Point being, they are focused naturally on the mechanical function.  And however much that gets you in pitch it is what it is.  In my experience that's about a half-step to a whole-step depending on the string gauge & individual instrument.  So, it's not like you have a lot of options here.

If you want to go up in pitch more than that you need a Floyd Rose (or other locking system) because setting a standard Strat bridge higher than that 1/8th of an inch will usually result in all kinds of tuning, intonation & action problems that typically make the guitar unplayable.  Most people just use standard string bending technique to go up in pitch.

Likewise, the distance down is what it is.  Typically the low E string will travel down about an octave.  A string about a 6th or 7th,  D string about a 5th to a tritone, G & B strings about a 3rd, high E about a whole step.  That's just a natural function of the string tension with a standard (non-locking) nut.

So, again if you want to go further down you need a locking nut system because that will allow the strings to go completely slack on the way down & about a 3rd to a 5th up.  See Vai, Satch or other modern players with locking system approaches.

Does that help?