Do what thou wilt shall be the whole of the Law
for my money, libers V and XXV kick the collective asses of the old aeon rituals up and down the sidewalk at high noon with crows overhead and pigeons underfoot.
i will say, though, that it really depends on the symbol set you're using. if you're doing greek symbolism, there's no replacement for Liber XXV. if you're using the NOX formula even a little bit, i HIGHLY recommend doing V and XXV both daily.
if you're using, say, norse symbolism none of the above are really appropriate, and you should just damn it all and write your own 😉
Love is the law, love under will