Drop D is fun, especially with some distortion. I like open tunings for clean with chorus effect, although I usually don't know what I am playing, but I hate retuning. One of my excuses why I need more guitars. Multiple tunings of each guitar at the ready.
I am still a little confused on 12 string tuning. Most twelve strings are tuned to D (two steps down on all strings, not just a dropped E to D), but transcriptions usually show them tuned as standard and no mention of capoes, nor have I seen anyone using one. Maybe I just didn't notice?