Why do you worry about having to factor in the DM?
A good DM will not stop you from attempting what you want to do, provided what you are attempting is within the bounds of reason.
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A system that lets a good DM do that to the best of their ability is a system which in turn and as a direct result, empowers the players.
Giving a DM more of a free interpretation actually does the opposite of what you are suggesting, by opening up the world, giving more options to the creative players who do not feel bound by what is written on their sheet. THAT is player empowerment.
I think there are at least three ways in which loosening the reins on the GM can limit player agency.
First, if the rules don't stipulate the DCs for various actions, that makes it harder, as a player, to build towards success in those actions. In this respect, 5e is less loose on the GM than 3E when it comes to combat (in 5e the GM is much more constrained in setting NPC/monster ACs than is the case in 3E), but generally more loose when it comes to non-combat DCs (there aren't the long lists of DCs that are found in the 3E skill rules). I think comparing to 4e is harder because the two systems tend to use quite different methodologies for setting DCs (in 4e DCs are generally set in a metagame fashion, by reference to the "level" of the NPC/monster or the ingame situation, rather than by reference to infiction considerations).
Second, if the rules don't stipulate the consequences of player action declarations in mechanical terms, that can make it harder for players to know what their PCs are capable of. An example (plucked more-or-less from the air) would be transmuting rock to mud. In AD&D the exact consequences of this for NPC mobility tend to be left up to GM adjudication, whereas 4e is much more likely to spell out that sort of consequence by reference to mechanically-defined conditions like
difficult terrain,
immobilisation, etc. (In AD&D the
web spell is defined in this level of detail, whereas TRtM is not.)
Third, if the rules don't establish conditions for
finality, then players often can't be as confident in making action declarations and extrapolating consequences. In 4e, there are rules for finality in combat (0 hp) and non-combat (skill challenges). 5e - like AD&D and 3E - tends to have the former, but not the latter.
I think [MENTION=59096]thecasualoblivion[/MENTION] is mostly expressing concern about (1) and (2).
the designers have said "Rulings over rules". But all previous editions were meant to be played that way as well (maybe not 4e; I'm not familiar with it enough to say.)
And you have yet to give a single example of where the rules are insufficiently codified. (Which is ironic, because there are some spots where that is the case...I could name a few myself. But I doubt 4e was free of these nebulous areas.)
For my own part, there is a marked difference between 2nd ed, which expects outcomes in the fiction to depend mostly on GM adjudication and intuition; and 4e, which expects the GM adjudication to take part at the point of
framing rather than
resolution - and gives strong guidance to the GM at this point of framing - and then expects
resolution to tell us whether or not the player gets his/her way.
At least as I read 5e, it leans more towards the 2nd ed approach. Whereas 4e is (again, as I read it) much closer to more "contemporary" systems like Dungeon World, Burning Wheel etc. In terms of my (1), (2) and (3) above this is about
finality. 5e, at least as I read it, tends to leave finality as an issue for ad hoc GM adjudication (except when a creature has been reduced to 0 hp), which I think is an issue for player agency.