In my mind Valve needs to give TF2 a new Engineer vs Spy update.
A new PDA with alternate build choices:
Replacing the teleporter entrance are three launch pads which send the players a distance/height of a double, then triplejump after leveling it, the engineer sees where the players will land in order to plan properly. It would somewhat resemble a smaller version of the aerial faith plate from Portal 2
Replacing the teleporter exit is a straight wall shield which is slightly taller than the Heavy (the tallest class), this energy shield blocks attacks in both directions but not visibility, it has a set amount of energy which slowly recharges, but cannot be built up by an engineer repairing it. Damaging the shield takes down the energy. Can only be sapped from the inside. Once the shield is down, it's easy to destroy, easily destroyed from the inside via damage as well.
Replacing the Dispenser is a Field Amplifier, which increases the rate at which charges generate within it's field of influence, the field can be made bigger by upgrading it, but not much faster and will not stack with others.
Replacing the sentry gun is the laser sentry, a smaller version of the one on gravel pit. At its first level it is as small as a minisentry, at its second it pushes back steadily and lights the target on fire, at the third level, killed players disintegrate like with the Cow Mangler 5000. Swings about slower than the regular sentry until it reaches level 3.
And for the Spy:
Slash and Dash: an smaller English-style bowie knife which increases a spy's movement speed to almost that of a scout while reducing the spy's hitpoints and the size of its backstab field - gotta be exactly behind the enemy.
Another great idea for a spy item is one which, when a spy is disguised, the spy's real shadow is seen, but you cannot bump into them when they are disguised. This way Spies have a new means of confusing and attacking enemies.
A new Electro Sapper which slides on the ground and when it hits its target activates causing an area of effect sap (like in Meet the Spy), one which is easier to remove but can stop multiple targets at once. The Slip and Sap would require a flat enough surface to work with and would give the spy a target of where it will be going illustrated in the manner that Engineers see their soon-to-be buildings. It would require a recharge so if the spy misses, they're out of luck for at least 30 seconds. The use of the Slip and Sap would be visible so a team that keeps their eyes open could easily spot the spy who launched the sapper.
Another Sapper to add in is one with a delay - this allows a spy to do a run-by sapping and leaves the Engineer with a hard time pinpointing the culprit.
While I am changing the entire game, how about:
For Medic: überraschen/Überraschung - to suprise/a suprise - This medigun, when the uber is activated, cloaks the medic and target and increases their speed greatly, the target firing a weapon ends the uber outright, this allows the target and medic to sneak into surprise attack locations and get the jump on the enemy and take out engineer nests in new and exciting ways.
For Sniper: the piece of piss: a stick with a pissy rag on it, little dangly bit jiggle boned that hangs off it, like a Jarate Boston Basher, it Jarates the Sniper if they don't hit someone. Spy needs to get a new achievement for attacking a Sniper and then the Sniper jarating himself.
Pyro needs a new flamethrower, one with two firing modes and no air blasts. First firing mode is a more focused one than the standard Flamethrower, more like a real flame thrower it goes forward a fair distance in a straight line - this mode deals higher damage at reduced ammo use because it is a more focused fire. The second fire mode, using the right mouse button, causes a switch to the nozzle and suddenly it's firing in a different spread. This second mode uses more ammo, fires a shorter distance and in a wider spread than the stock Flamethrower - it's the spychecking and ambush mode. In order to make this one visibly distinct, it would need a team-coloured paint job, as it is it's kinda hard to distinguish pyros.
Phlogistinator needs to lose the power up during their taunt, the weapon was over powered before the most recent patch, with this uber-taunt it is ri-goddamned-diculous. The Phlogistinator has taken over from the Backburner in all ways, it is horrible for the older weapon to be cast aside like this for a stupid over powered weapon.
And why not implement those damned grenades everybody's got on them already? It would totally change up the game.
All kinds of grenades-like things. Proximity bombs for Engineers, dynamite for Demos, smoke bombs for Spies, caltrops for Scouts, flashbangs for Soldiers, incendiaries for Pyros... Triplines to activate claymores for Snipers.
I do hope that Valve's slow burning competitive TF2 works out well, I would like explicit game modes of Highlander, 6v6, 4v4, Casual, Saxton Hale, MGE, Prophunt, and MvM that you pick from the starting menu.
And while we dream global player stats which would be used for generating teams on all servers that are not set as Casual. Balancing the top players between teams with no stupidly unbalanced teams popping up to waste 5 minutes as one team gets smoked.
Nothing too big, surely Valve could whip it together in a few weeks if they really wanted to.