What's always kept me from getting into DADGAD and other tunings is that playing in a session you have to keep switching keys, and I can't do that with any flexibility excpet in standard tuning - especially since I also like to be able to capo up and play in a higher voice, pparticularly if there are other guitarists as well.
Working out what different chords are fitting at different frets in different keys with a different tuning - those are too many differents for me