One screen is way too big! Make each function do a single thing. Even in verbose languages, you should be able to get most of them down to 5 lines or less - and this isn't actually difficult (except for coming up with names for all of them) the transformation is actually very mechanical, so much so that if you're using an IDE it can probably "extract method" for you, but even doing it by hand is trivial once you get the knack of it.
Indeed. 25 is the maximum - mostly the shorter, the better.
Though at least for me there is somewhere a limit (2-3 lines?) where the returns start to diminish - there's more noticeably more typing involved, and more mental context switching while debugging.
