As far as using the encounter guidelines, something that the DMG 1 DID do right was in their "monster packets" (I think that's what they were called). You were never, really, supposed to use 5 of the same creatures of the same level. The DMG actually strongly advises against this. By and large it was one or two creatures a level or two above the party and the bulk of creatures a level or two behind.
If you follow that advice and then add in the bulk of baddies as skirmishers, grind goes away and you get really interesting encounters.
Now, the initial WOTC modules were pretty bad. Naw, that's not strong enough. They were outright crap. Far too many soldiers, and encounters with not enough diversity. You have to mix it up. Heck, compare the WOTC modules to the Robot Chicken live play adventure that was used - miles apart. And, pretty telling that ...whatsisface... didn't use any pre-packaged adventures for the live play broadcasts.
Look, compare initial release 3e with even the second release PHB. There are huge differences. People gloss over them because the first release PHB's weren't in circulation that long. The second and subsequent releases were only months later and we went to 3.5 very soon after that.
The 4e PHB (and core books) sold extremely well and were never changed. So all those revisions and whatnot get buried. It's a shame that WOTC didn't spend another year developing 4e.