I'm with the OP and others on this, and have been semi-ranting about it elsewhere.
If they make one more arch-villain with any kind of super-weapon or ship, and with the threat of (shock!) destroying planets, my head will explode in the theater, leaving nothing but a headless corpse, holding its soda, blood spurting a la Monty Python.
I'd pay the price of admission just to see that!
The funny thing about all this is NONE of the movie villains have been very good. That includes the one from Hamfest '82.
I don't think that. Khan was the perfect pole to Kirk. The Klingons in STIII were true
Klingon bastards. The probe in STIV was fairly ingenius. Sybok was a great (non-planet destroying I might add) villian concept. Gen. Chang was allright, though the actor never sold me on his being a Klingon. Then we have Dr. Soran, who is, as I saw it, a sci-fi metaphor for a crackhead. A little two-dimensional, boiling down to the madman that must be stopped, but we understand why he is like this. Then it's the Borg Queen - creepy, sexy, horrifying, beautiful - a fascinating character. With INS we have several shades of villain characters present with Ru'alfo, his brother, the Starfleet Admiral. Then in NEM we have our cyberpunk Picard-boy bent on self-destruction, but not before he gets a little virtual Troi. Then finally, Nero, Romulan miner lost in space with his miner-buddies. He's lost his home & family, somewhat cracked, and the voices tell him that only when all the Federation planets are destroyed will the angels stop crying.
Actually, if they'd set up Nero a bit "crazier", he'd have made more sense.
Looking back over these villains, I can't really say any of them have been bad character concepts. But the "madman destroying a planet" button has been pushed too many times: If Khan gets Genesis. If Kruge gets Genesis. If the Probe doesn't get told what to go do with itself. If Soran launches the missile. If the Borg stop FC. (Ok that's not destroying the planet, but the life as we know it, Jim.) If Ru'Olfo manages to do his thing. If Shinzon makes it to Earth. If Nero makes it to Earth. In all of these the Earth is directly threatened in TMP, STIV, FC, NEM, and STXI, and Earth-like planets threatened in GEN & INS.
That's 7 of 11 films about saving planets, and 5 of them in a row! The villain characters have been pretty interesting, it's the "save the world" angle that's gotten tired.