Who's the ideal person for you to spend your life with?
First and foremost, a man who wants to spend his life with ME, not an easy requirement. And then after that it's an assorted bag of things, no one of them terribly vital or a deal breaker, with money not part of them.
Other than he not be a shiftless moocher who can't support himself on his own, and who only wants me to live off MY limited money. And no drugs, drunkenness, maladjusted personalities or criminals. (Line from the movie Priscilla, Queen...: "Well, that doesn't leave us much to talk about then, does it?")
But it's nice to have similar interests & tastes in various ways (music, food, furnishings, entertainment, vacations, cars, etc), all the things you share and do together. And a true partner, a teammate, the guy you do everything alongside, without whom you feel incomplete when he's not with you.
And finally, a similar sense of humor is high on my loose list. Compatible with my silly and absurdist sense of comedy, who maybe can play along. People used to tell my late partner & me, and now my current guy, that we'd make a great professional comedy team. We actually go into ridiculous spontaneous comedy routines together.
Our improvised banter is a surprise to many couples, especially the younger ones, who think old guys like us have no humor left in them, and certainly aren't supposed to openly express it. While we are amazed how dull, unimaginative and actually staid some of the younger couples are, kinda a role reversal. Yeah, they can get wild, but that's not humor, that's just behaviorally letting off steam. The last few generations seem about as funny to me as an evening at a wake.