Please define "fun."
Heh. I can't. Each person has to define that for themselves. I find it fun to to wade my way through orcs, chopping them in half with a weapon or blowing them to bits with fireballs, each round knowing that it might be my last if luck doesn't go my way or if I don't carefully plan my position and tactics.
I don't find fun any round that works like this: "I trip him, go." or "I'm still in a grapple. I attempt to pin him. Failed. Go." It becomes even worse if this is the 4th or 5th round of attempting to pin or attempting to escape a grapple while the other members of my group have killed 1-2 enemies each in the same time. It makes me feel kind of like my rounds are wasted doing nothing.
I admit, I alo find UFC boring. However, Brazilian Jui-Jitsu matches (and Judo when it enters the ground fighting phase) can often be rather interesting to watch, like human chess. I'm not sure why there's a difference in (at least my) perception of UFC grappling and when it's done in those martial arts, but it's there.
Glad to hear you enjoy it. It may even be somewhat interesting to watch. I haven't, so I don't know. Still, it just doesn't "feel" like heroic fantasy to me. I expect my fantasy heroes to quickly dispatching foes with their weapon. Almost any realistic or semi realistic depiction of grappling still involves extending the length of a combat by a number of rounds, and spending many of those rounds positioning. It causes the aforementioned situation of "This is round 4 of attempting to pin the enemy. All of the other enemies were finished off by my allies by sticking swords in them. I haven't heard my opponent at all."
IME, that's the default kind of combat the players are inclined to go for, and the most fun combats are when environment, traps, and clever tactics prevent either them or the enemies from merely rushing in and hacking.
I agree, that sort of stuff is fun. I try to use it when possible. Still, the goal in those situations is still the same. You want to hack your enemies up, you just need to be careful about it.
It is hard to do, and 3E was far from perfect. But at least it tried to handle it. Any "realistic" grappling rules will be incredibly messy and complicated...much like grappling itself. I don't know if it's less dramatic to go for arm bars and desperately try to break out of choke holds compared to swinging around a sharp piece of metal, though.
I do find it less dramatic. When you are dealing with a sword or a fireball, everyone knows those sort of things kill people. In one hit(in real life, maybe not in the rules). So, you get that sense that if you didn't just barely get out of the way of that last strike, you'd be missing your head. With grappling, I normally get a sense that if you fail your grapple check this round that the enemy will move your arm 2 inches downward. And if you fail 3 more of them, he might get it behind your back. Then it'll hurt for a while. In a couple of minutes of that, he might be able to break your arm.
Fighting should be quick and deadly.
Depends what movies. In a European fencing match? Probably is a fight-ender. Jackie Chan gets disarmed all the time. Granted, he fights unarmed and improvised, but sometimes he also retrieves the lost weapon safely via some cool stunt. It's also often times part of the fight in anime. The whole "lose your gun only to desperately dive after it and get the winning shot off just in the nick of time" scenario is so common, it's probably a trope.
Yeah, I tend to view fighting as more like Braveheart, The Princess Bride, Willow, and so on. You get disarmed and you have no way to defend yourself and you get run through. I admit, it DOES happen periodically. Most of the time the enemy stops to gloat and doesn't notice the hero pick back up his sword or he gets distracted for just one second and the hero leaps over and picks up his sword. But the actual combat tends to end at the moment of the disarm for at least a while. I still think it's best modeled by what happens when you reduce an enemy to 0 hitpoints and decide not to kill him. It makes for a perfect situation. You disarm him, you hold your sword to his throat. The enemy never "goes unconscious" and instead "wakes up" as if the PCs had taken a short rest. If you stop watching him for a moment, he has the opportunity to get up and grab his sword and continue the fight. But as long as you keep him covered, it's safe.
As for Jackie Chan. But he gets disarmed just to prove how good a fighter he is without a weapon. He doesn't really count.
Sunder is problematic. Still think it should exist in some form, though.
This is one I care the least about. Weapons don't break that easily. Certainly not from just attempting to break one in combat. Hitting someone's weapon over and over again should never be the slightest bit effective when compared to attacking them with your weapon instead.
Wait...why can't it just be a basic melee attack for no damage (or maybe unarmed damage w/ no ability modifier -- cue in Monks to be awesome trip-monkeys!)? The benefit is it leaves the foe prone. How crappy is the prone condition in 4E? I know you don't provoke for standing, but how low is the bonus to hit, again?
In 4e, you get Combat Advantage against prone people. Which is +2 to hit. It also doesn't stack with other ways of getting combat advantage like flanking, stunned, dazed, etc. Which means it's useful to knock someone prone, but if you already have any CA against them, it doesn't do anything at all. Besides, +2 to hit isn't huge.
The point is when you put something into the game it has to compare to the at-will powers in 4th. There is a cleric at will that attacks at range and does damage plus gives an ally +2 to hit for one attack. Which is ABOUT the same as what tripping someone does.
But if you had a choice between hitting with the cleric at will power and attempting a trip that only did 1d4 damage and knocked them prone, you'd ALWAYS take the cleric at will. If you have the choice between hitting with the fighter at will that did normal damage for your weapon AND moved your enemy into a possible flanking position, you'd never trip.
The name of the game is damage. So, for any attack to be effective, it needs to do damage or cause an ally to do enough damage to make up for your lack of damage.
Trip is the only attack I could somewhat see as a generic maneuver to all classes. In fact, I don't really have a problem improvising this as a Str vs Fort attack that knocks an enemy down as long as it is within 1 size category as you with no damage. However, as it stands, that ability is so weak in 4e that almost no one will use it.