So have I. We can go around and around in circles. For every thing you come up with a smart fighter and an imaginative player can counter without the need to nerf anything.
If a fighter can't beat a Wizard then the player is playing the fighter wrong or is the other player is smarter than the player who's playing the fighter.
And by the way, a simple bag of flour kills invisibility. For every step a Wizard makes a fighter can make and stay within reach. And pole arms have longer reaches than a sword.
And with the right maneuvering can make the Wizard fall into a ten foot spike laden pit which could cause poison and disease damage to the Wizard.
Or cause him trip over the rogue who's ready to trip him from behind.
Or simply use an action to trip a Wizard. Whoops, the Wizard's now suffering from being prone.
Right.
Even if I were to assume that everything you said above was fair and accurate, every last one of those points assumes that it's the fighter who is hunting the wizard and gets the drop on him. If the wizard gets the drop on the fighter, what happens? The fight's over even before it's begun. The fighter can not disrupt the wizard's spell by any of the means you mention because he didn't know the wizard was there. Spell resistance from items ain't gonna work - far too expensive for the effect.
And who's more likely to be able to get the drop on the other guy? The fighter with his 2+Int modifier skills/level, or the wizard with his 2+Int modifier skills/level (and remember Int is his primary stat and will therefore probably exceed the fighter's),
and spells like Change Self, Detect Thoughts, Invisibility, Scry, and Teleport (to pick just a few obvious ones).
In short, if the fighter gets the drop on the wizard (as he needs to for your scenarios to work) or even meets him on equal terms as in an arena, then the wizard has
already made huge mistakes. And huge mistakes in a contest that would only start to be fair if you tied both hands behind the wizard's back to prevent him casting spells. (Even then he still wins on the skills - and isn't wearing heavy armour).
As for tricks like bags of flour, you can only get the wizard with the bag of flour if you already know where he is. And you have the spellcraft to realise that when he disappeared. If he disappears how do you know he didn't
dimension door somewhere out of your line of sight? Throw your bag of flour to counter his invisibility spell and he
holds you or
hideous laughters you or
flesh to stones you or
baleful polymorphs you or whichever other takeout he's prepared. (Some I wouldn't recommend against a fighter admittedly, but that's why the wizard has spell slots). And as for maneuvering the wizard down pit traps - remember that the fighter has to cross the ground to the wizard not the other way round. Meaning that the chance of getting the other guy down a pit trap is an advantage to the wizard, not to the fighter.