Well all F tuning is doing is taking the root, adding the 5th, and then adding the third degree of the scale. Very simple, but sounds amazing. I like taking chords and building on them 'beefing them up' if you will. As well as going down or up chromaticaly, raising or lowering each part of the chord each time, which will eventualy come to a resolution. Sometimes I mess around with chords, my favorite is I, V,mV, IV, augmented IV, II, I. B)