Do not underestimate the extra-dimentional beings, you would be like a fun looking insect to them. The material plane is special and you may some day be more powerful than an ancient dragon or lich king, but that would be like saying you are the biggest minnow in your pond. There is a tenuous standoff between warring factions and those who protect the material planes but even they are pawns in a grand match. The very ground you walk on, the air you breath, the animals you eat to sustain yourself are owned and fiercely fought over. You are allowed to use them as much as a cockroach is allowed to use the sewer.
There are always weaknesses, even among gods, and mortals of this realm can ascend, but you specifically are immortalized in material form, again, unless your final form can survive the vacuum of space or the molten core of a planet, or prevent being forcibly moved to another plane, in other words, unless you can be immune to destruction, you will always be at their whim. This is the curse of 20, the choice that is made to give something up to atain something greater but in doing so you lose the one thing you hoped to perpetuate.
The material plane, as tame as it is, is not a coincidence, it is purposefully done, and beings beyond comprehension made it so, and keep it so.