These are good faster tips. The OP also says "further" which includes an element of comfort.

I don't know that aiming for narrower tires is going to always be the a win in the further category. Lighter, higher quality tires can be such a win. For the usual road and groomed trail riding you don't need any kind of aggressive tread.

Someone's already pointed out that slamming the handlebar height alone may not be further win for all riders. Bar ends can be a compromise that lets you have a lower position and a more upright one. For me "butterfly" trekking bars are another further mod. You can set them up so that they are on a 45 degree angle with a long enough stem/top tube so that you can get lower position like drops (though your hands are perpendicular to the stem on parallel to it in this lower position) as well as a higher position like the tops of a traditional road bar. Some also set the trekking bar flat and report they can do something like an aero bar position. Whatever, one nice things about butterfly bars, more hand positions can aide "further"