Unfortunately, that's the kind of creativity that I absolutely don't like to see in my games. Stone To Mud may be a borderline case, there's been more extreme 'creative' abuses of spells in the past. This kind of creativity is part of the reason why 3E became so complicated because it tried to prevent any loopholes.
Thinking of a clever trick that allows a spell to be way more effective than its level indicates shouldn't be possible, even if it seems to be fine by RAW. To exaggerate the point:
Being able to turn a cantrip into an auto-kill spell is not desirable.
Creative uses of spells must always be in line with the spells' level. And it's not limited to spells either. There's a reason the 4E DMG suggests a damage progression for freestyle maneuvers. Thinking out of the box is fun - provided it doesn't imbalance the game.
The thing is that "level" wasn't meant to imply some power rating, but power expenditure.
A level 9 spell took a LOT of power from the mage to create it. Often those effects could be mundane, or tremendous hazards for anyone near it.
The shift is that level is now considered the amount of damage it can do.
Stone to Mud was placed at a level for it to do its job. Create X' sq of mud from stone. The fact the enemy was standing on stone and got trapped in the mud when it was turned BACK into stone was their own problem and poor tactics.
It also in now way imbalances the game because the DM knows EXACLTY what the players are packing, and should be able to be prepared for it. Likewise when the PCs and NPCs/monsters share similar, then the players know what the DM could be packing via the approved list of books that they are on their own to know what to look out for.
The false sense of balance in some power rating being now called level is flawed design. It limits creativity on every level. Basically turning the game of D&D into "Mother May I?"
The DM has a hard road to walk, and that has always been so with the powers of magic, and should be so in that a DM should be able to handle those cases of magic used in a new way. The whole idea of spells only for attack really sickens me more than any well thought out plan I had as a DM getting screwd up because a player outsmarted me. I love for players to outsmart me because that is where the DM gets enjoyment knowing the players have payed attention to both him and the rules, and found something interesting and entertaining to do for all the other players.
I appluad that rather than condemn it.
Care to list these 7 effects?
Because I can see powers that do...
Push
Pull
Slide
Force Movement
Heal
Give temporary hit points
Blind
Deafen
Daze
Dominate
Immobilize
Slow
Stun
Knock prone
Weaken
Mark
Deal Damage in the X[W] mode
Deal Damage via zones
Deal Ongoing Damage
Deal damage in other means
I see powers that allow for flight
I see powers that allow for teleport
I see powers that give bonuses to skill checks
I see powers that give bonuses to defenses
and I could go on.
What are these limited seven effects you are talking about?
& was a number pulled out of a hat, but your list is padded excesively with the same things over and over.
you have 4 different "move" effects. Push is Pull in the opposite direction. Slide is push or pull in the direction of your choice. All of them are forced movement.
1- Move
So while you can give the effects all special names for little quirks, many are still the same thing.
Move, Buff, Prevent from moving, etc, and you see there aren't really that many things there that powers do.
The point is that the powers focus on only 3 things. Effect, damage, or damage+effect.
In the case of the wizard directly, that is kind of silly. But it requires talking about rituals to fully discuss what a wizard is, and the fact that a wizard was halved to allow all classes to take some of his "powers" is another problem.
The effects wouldn't be so bad to have if they were not built for combat, like all powers are.
"Fly" is even designed with combat in mind for its duration, but at least it has a real timer added to it. to make it something more than another generic combat function.
It is one of the better designed powers because of that. But it needs to lose the Feather Fall effect and let people fall on their own like those forgetting the duration and range should.