I have all the new items from the War Update, and I have to say I have mixed feelings. I have serious balance concerns about almost all of the weapons.
Soldier "Scotland is not a real country! You are an Englishman with a dress!"
The Direct Hit may be overpowered, it's hard to tell exactly how much damage it does, especially with the patch that just changed how much damage it does. I'll tell you one thing: it does a lot.
The Buff Banner seems to be quite balanced. You have to get into the thick of it to charge it up, so it's a game of risk calculation: getting into that fight might get you fully charged, but it might kill you right before you finish charging, too. Once you actually trigger the banner, it's totally awesome. 14 seconds of mini-crits for a pretty large area is incredibly significant, especially when your own Direct Hit rockets are buffed to the point where you can one-shot snipers/scouts/engies.
At first, I had a problem with the Equalizer being so good, I'm against items that are purely better than their alternatives. At the moment, the Pick is technically not purely better than the shovel, as you can't be medi-gunned when you're holding it, but it is a lot better than the shovel regardless. Previously, the shovel was the least damaging weapon in the game, so I think soldier melee needed a boost. Now they just need to boost the shovel to make it an honest choice. (Have you seen a Soldier at really low HP plow through an enemy team? Devastating)
Demoman "I'll notify your Next of Kin... That you SUCKED!"
I'm going to skip all the lead in: Everyone knows there's an overpowered weapon in this update, and Valve better nerf it before the game is completely ruined.
The Grenade Launcher. It's good at close, medium, and far distance. It does enough damage to one-shot low health classes, and two-shot everyone but a Heavy. It's the most effective weapon against a Sentry Gun. The pills go faster than the regular Rocket Launcher, and are nigh-impossible to dodge, unless you're pretty far away. Even when you do dodge them, they stick around to deal ~60 damage to whoever is unlucky enough to stand in their enormous blast radius.
The Sword and Shield are essentially an enormous boost to the Grenade Launcher. If you get 4 heads with the Eyelander, you have over 210 HP, along with Damage resistance that essentially doubles your HP against most classes. You also go about as fast as a scout. This lets you use the grenade launcher with impunity, and still allows you an occasionally instant-kill with the sword. If anything gets nerfed, it's going to be this. (There are few things more frustrating than Direct Hitting a Demoman in midair, only to see you did about 40 damage.)
PS. There are a lot of new visual options that default to being disabled: Go into your advanced multiplayer options and turn basically everything on. The new medic stuff is really good, it shows you where people are even when they're not calling for medic, and being able to see how much damage you're doing is incredibly useful, both for gauging how much HP the enemy has, and to train yourself to be more effective.