Shemeska
Adventurer
In fact, I find it funny that you're basically arguing for limits. The Inner Planes of previous editions did not present as many options for a DM or players to explore as the current setup, which is the point.
The hell they did. The inner planes of previous editions had more options than the hand-holding "Don't make it too dangerous! Then adventurers won't come to our extraplanar dungeon! Oh noes!" I see in the 4e planar design.
By stripping any serious level of hostility from some of the planes, you water down the wonder and challange of actually adventuring in those planes, even as you strip depth and background flavor from the cosmology.
By no means was the elemental plane of fire just a blank, endless, YOU DIE NOW! plane of flames. Just skimming The Inner Planes by Monte Cook from the later days of 2e that's blazingly clear, even when the book happens to be narrated by a crazy slaad named Xanxost. In the 1e/2e/3e Elemental Plane of Fire you could have adventurers step through a portal and trudge across a plain of compacted ash, intermingled with the crumbling bones of dead Azers, slain centuries ago by a theocratic empire of Salamanders. The PCs could struggle across the landscape, crossing lakes of cooling lava covered only by a thin crust, sweating from the heat as they search for the ruins of the Azer capital city where a longstanding campaign antagonist searches for a relic of Imix, once worshipped by those same Azers, hoping to use it to summon the Elemental Prince to the prime material.
The Elemental Plane of Fire wasn't just a monolithic stretch of fire. And saying that it was displays either an ignorance of previous editions' material on the plane, or a blatant misrepresentation of it.
The 4e cosmology by its nature is placing limits by what the design team feels is proper for your campaigns, and in the process it's happily twisting previous campaigns to fit that sterile, homogenous view. Nothing in the previous cosmology from 1e/2e/3e precluded anything from the 4e planes from happening therein.