So I was morbidly curious about what you meant, so I looked it up:
Whoopi Goldberg faces a fresh round of backlash after her latest historically inaccurate statement about the Holocaust, which she claimed "wasn't originally" about race in an interview
Remember Ardra, the lady on TNG that pretended to be the actual devil to claim a planet by contract? "I could give you a night that would light fire in your dreams until you die," she offered Picard. Q could actually do that. Forget just shapeshifting into Troi, or dressing up as a prim and proper Englishwoman. Mere cosplay chicanery. Q could give you impossible experiences. Becoming the concept of orgasm. Geometrically impossible positions. Awareness of both bodies at once. The feeling of becoming a nebula and releasing all tension as you dissolve into the universe. Experiences beyond understanding that would shred your pitiful psyche, and you'd say thank you.
Are you sure you want a partner who can read your every thought? Also, Guinans got wisdom to doll out for the rest of your life, which will be far shorter than hers, barring unforseen circumstances.
In that order. Wouldn't want to spend a lifetime next to a mind reader. Guinan would be a wise, nurturing partner. Most importantly, Guinan can summon spirits and we all know who'd get a kick out of that.