a good thing to do[in standard or any tuning]is to make a diagram of the fret board,then you can work out all your different inversions.
   dadgad like some other open tunings, offers you the
possibility in d and g[ particularly] of making different inversions of modal dyads,easily.
one finger, second fret g string,dadaad.
two fingers, seventh fret g string,fifth fret a string,dadddd.
three fingers,fifth fret fifth string,seventh fret g string,fifth fret, a string, dddddd.
you would have some job doing the last two in standard tuning.
the opportunity to play power chords[dyads],with added sevenths ninths etc,becomes generally simpler in dadgad,and you have sympathetic ringing from the strings to add to the sound.
standard tuning is the most flexible tuning,particluarly if your song modulates.Dick Miles