Oh, I definitely have a legendary dinning hall for happy thoughts, I just don't designate it as a "meeting hall", to avoid parties.
I also don't allow my soldiers to carry food, so they get happy thoughts from the waterfall leading into the legendary dinning hall and so forth.
It's just the sculpture gardens that scare me, but I've honestly never experimented with using them to see if the happy thoughts outweigh the friendships made.
I do have one large family that I try and keep safe, although it just occurred to me, that perhaps designating a sculpture garden to this family might keep the kids out of trouble.
Do people throwing parties only invite the dwarves they know? Or would that put my military in danger of making friends?
Until I get patrols set up, I do that as well, putting barracks for training in choke points, so any hostiles are greeted by dwarves looking up from sparring with big grins on their faces, ready to test their mettle and their metal.
I agree with doing as much real combat as possible for experience, sending a squad out as hunting party on occasion. I don't use hunters, so the military can do the hunting, gaining skill while providing meat to the fortress well.
i'm not sure about how parties work... if the host gives "invitations" or its just any idler available. i have none of my statue gardens assigned, but i do have a lot of them. my cryps are 4 5x5 cells arranged around a 3x3 stairwell. a total of 2 cells are used for noble tombs, and have a valuable coffin, and 4 statues, one designated as a garden. all the other cells have 23 coffind allowing citizen and pet burial, and 2 statues, one designating the entire space as a garden. i have four complete units (16 crypt statue gardens) i have my dining hall and well. i then have two other statue gardens where i want civilians to hang out, one on the first floor of my tower, so someone can pull the levers there on short notice, and one at the ground floor of the king's keep, so dwarves are available for my king and duchess to socialise with. and so that they socialise with each other. i'm trying to unify succession, so that i have a clear and robust line of duke-kings in the future. failing that, they both need consorts. i plan on this fort going as long as it can, and as i'm self sufficient, and could technically survive at least decades totally walled off with minimal user interaction.
no one in my fort has many friends. the two that pass being mayor around nowadays are both former children with exactly one friend each (come to think of it, it might be each other), there are a few other dwarves with one friend.... the duchess. out of her six listed friends, only no more than three can still be alive. perhaps in addition to everyone being busy, my large number of meeting halls keeps idlers and children spread out, so that no one really socialises. i've noticed a lot of my migrants have rust on their social skills.
i use hunting, and hunt with my military at the same time. my hunters are all off-duty marksdwarves. having a bunch out at once is nice, they'll sometimes spot thieves and ambushers for me.