I wonder how they are reducing the Christmas Tree effect. It isn't enough to rebalance monsters to allow people to be effective against them without a boatload of "standard" magical items, it's also neccessary to somehow limit the available and/or power of such items.
A general idea I had: Magical Items that broaden a characters ability are usually interested, but not neccessarily making him more powerful. Items that just add to an existing ability are alway powerful, and quickly become a neccessarity.
So, here are some examples of items that come to my mind:
Flaming Longsword: The Longsword deals fire and slashing damage. If an opponent doesn't have resistances to both, he will suffer the fully rolled damage, otherwise, he uses the weakest of the two resistances. Once encounter(?), the wielder can make a fullround action and throw a small fireball (Weapons regular melee damage, but fire only) with a 20 ft range increment. The longsword sheds light like a Torch, and can be used to set inflammible items on fire.
Yes, the weapon is a bit more powerful then a regular longsword. But mostly, it just gives more flexibility. You don't rely on its bonuses to be effective.
Gauntlets of Ogre Power/Belt of Giant Strength:
Gauntles of Ogre Power add a +2 bonus to Strength, but don't increase your Strength beyond 16.
Belt of Giant Strength add a +4 bonus to Strength, but don't increase your Strength beyond 18.
These Gauntlets of Ogre Power are not neccessary for most Fighters, but they serve well to compensate weaknesses of other characters. A regular Fighter can spend his money on other items (if items can still be bought that easily), maybe an Headband of Illithid Intellect...
It is a bit of a throwback to earlier editions - if I am not mistaken, earlier versions of the Gauntles increased your strength to a fixed amount - but from a balancing perspective, they will probably work a lot better. They don't make your own statistics a non-issue.
An interesting question is to figure out how you eliminate the need for "pure +x" weapons (or wands), which are apparently still part of the 4th edition. Maybe they just compensate a low BAB/Caster Level?). How about Cloak of Resistances +x or Ring of Protection +x? (Maybe they work entirely different now? Cloaks protect against energy damage, Rings protect against spells?)