So will I actually be able to make use of the 74F's? If so, what would they be useful for?
There used to be a lot of circuits based on 7404 type inverters; you can coerce them into oscillators and such. I don't know if the F04s would work in such circuits.
Nowadays, not so much. Your F04s are probably somewhat useful as high-current drivers. If I read that datasheet right (and it's somewhat weirdly stated), the outputs should be capable of sinking 50 to 100mA (vs 20 to 40mA for the AVR outputs.)