1) Don't build assumptions about what magic PCs have into your challenge ratings or appropriate-level monster defenses. No need to keep up - no need to go with upgrade after upgrade. People will still want the upgrades to a certain extent, but won't feel they're so "mandatory". 4e may have relatively weak magic, but they're still built into the expectations of the system.
The problem there is that characters with magic items will be more powerful than characters without, and will likely make "challenging" encounters too easy. For adventure-writing purposes (where the adventure isn't for your personal gaming group -- i.e., you know nothing about the PCs that will undertake it), you can't know how hard to make encounters.
That makes pre-written adventures less valuable to GMs, meaning they'll sell fewer of them, meaning they'll need to sell more sourcebooks, leading to more power creep and a faster edition turnover; then the sky falls, the Mayan calendar ends, Michael Bay and Roland Emmerich team up to make a movie together, and the CGI/explosion singularity occurs, and we all become slaves to our new computer overlords.
More seriously, maybe they should silo "combat" off from "utility" more. The primary balance concerns revolve around combat; if something has little-to-no effect on combat, then they get as weird and wahoo as they want, without worrying about breaking something.
Clever players will be able to turn utility powers into something useful in combat, but that's not a bad thing -- they're likely to be things not clearly delineated by game mechanics, so page 42 and GM judgment can handle it.
In 1st edition, the ultimate combination was belt of giant strength (especially storm giant!) and gauntlets of ogre power. Every fighter longed to have both, because with them he became an almost unstoppable force (a vorpal sword would just have been frosting).
Nah, you needed the
hammer of thunderbolts to make the girdle & gauntlets combo effective; only that one weapon (in the DMG; there may have been other items in adventures, there certainly were in home games) allowed the girdle & gauntlets to stack. Otherwise, 19-25 Str from the girdle took precedence over the gauntlets' 18/00.
I never saw the combo in action, either, though there was a character or two that got close. (Some of the groups I were part of were very fond of high powered AD&D characters. Mmm, 1e psionics...)