Saeviomagy:
"If one of those spells is teleport, then it's an 8th level spell."
Your point is?
"For an 8th level spell slot you could have fired off a symbol spell."
If I have more than one 8th level spell slot maybe I'll do that too. Or maybe I'll use that other 8th level slot for a horrid wilting, since I can do that from 1000' away (more on this latter). Then I'll bounce out on the same round. If I can also quicken spells, maybe I'll do that too. If you haven't nerfed haste, maybe I'll toss something else while I'm leave.
"And this is a good tactic how?"
I just hit you with my highest level spell, a quickened spell, maybe an extra spell from haste, and up to 4 other 1st-4th level spells and teleported out before you even knew I was there or could do anything about it.
"You'd need to be guessing where your opponents were going to be."
That's called reconaissance. Anyone with decent stealth ability and fair access to divination spells ought to be fairly well advantaged there.
"You'd still be spotted and heard when you cast the spells, not when they take effect later. "
Excuse me but no. Any character built around this concept would have taken that into account. If I'm casting 8th level spells then I can hit a target with a medium range spell from 250 ft (Cloudkill, Confusion, Glitterdust, Hold Person, Evard's Black Tentacles, Dispel Magic, Dominate Person, Stinking Cloud, Web, Wall of Ice, Wall of Iron, Wall of Stone, etc.). I can hit them with a long range spell from 1000 ft (Fireball, Pyrotechnics, Silent Image, Telekinesis). Both are more than sufficiently far away to conceal myself in some fashion and make it more than difficult to hear my verbal components. Under the (broken) spot/listen check rules, I dare say that even an epic level character is going to have a hard time noticing me from long range - but any reasonable rules are going to make someone 300+ yards away with 75% cover or better a tough thing to spot. And unless it is perfectly quiet in the environment, even if they did hear my distant verbal components it would be an extraordinary feat to hear and distinguish the sounds of spell casting over other normal sounds of the city or any other noisy environment. I doubt any ordinary character could make the combined listen and spellcraft checks necessary to do it, and that's assuming you didn't force a wisdom check to notice the sound as unusual in the first place.
"Your opponents are going to move about."
Then I wait around for them to start doing something that involves them not moving for at least half a minute or so - cooking dinner, praying, memorizing spells, talking with a merchant in the market, eating dinner, dressing wounds, sharpening weapons, sleeping, releiving themselves, bathing, ect. I can be pretty sure to encounter such a situation eventually for any realistic campaign against any sort of target that this sort of character is designed to go up against.
Even if I misjudge and they move, I just move in response and all the target sees is that a spell has blossomed mysteriously were they just moved from. I'm patient. I can wait until their gaurd is down. I can wait for weakness. In the mean time whatever advantage I've lost in surprise I've more than made up in confusion and paranoia.
I definately get the impression you've never played a particularly stealthy character.
"Hell, they'll probably kill you while you fire up all your sequential spells."
Yes, I definately get that impression. I also get the impression that _in the sort of campaigns you play_ you can't see a role for such a character on either side of the table.
"See? it's useless even for setting up an ambush unless you use spells without a V component."
I gather you haven't set many ambushes either.
I'm sure that there are a great many other tactics. I don't deny that. Better tactics? That's pretty subjective. Depends entirely on what you want to do. Better tactics for someone working as part of a team? Almost certainly. Better tactics for a single person minimizing risk to himself? Maybe, but this would certainly be a potent weapon in such an arsenal. Better tactics for someone working in an extremely hostile environment who can't afford to be linked to the attack? Probably not. Delaying a spell and having the ability to walk away or stack spells up is potent enough that I think it is clearly broken at +0 - which some people have suggested, and potent enough that I feel it is far too powerful at +1. The lower you set the penalty this the worse the array of spells becomes. You set it low enough and all the sudden you are getting hit by massive attacks simulataneously, or I can afford to Silent Spell those spells and take even nastier direct damage spells with only close range.
I never said that this was an excellent +3 spell level metamagic feat - but neither does it deserve a 1. But it isn't good idea to make it +1 either. At +1, I start imagining silent, still, delayed spells. *shudder*