Hit Roll Aliasing, D&D's biggest issue

I never though I'd use digital signal processing terms in D&D, but here I am.  There are various issues with the D&D gaming system.  The one I believe stands out is combat.  Clearly it has the most convoluted set of auxiliary rules, addendums and tables.  Over the years I've though about what the issue was.  What was the core problem.  Now if I have to put a word to it it is aliasing.  Aliasing is, as wikipedia puts it, " an effect that causes different signals to become indistinguishable [from one another]" . In D&D the d20 system makes it difficult to tell events from one another.  Just like a low sampling rate makes it impossible to digitalize a high frequency signal, so does the d20 system fall short in representing all the events involved in a sword swing.

D&D tries to cram all the events, effects and outcomes in a single number called "to hit roll".  Which is more like the "to damage roll" since once you succeed in it damage is rolled.  If it were really a hit roll it would not include attack bonuses, defense bonuses, parry and dodge bonuses, etc etc etc.  You add all the good things and the bad things and then some, put a d20 roll into the mix and come up with a value that somehow represents your success at making someone very miserable.

We are basically adding a bunch of signals into one value:

Attach Bonus = Base attack bonus + Strength modifier + size modifier

Armor Class = 10 + armor bonus + shield bonus + Dexterity modifier + size modifier + {Enhancement, Deflection, Dodge etc bonuses}

Then "sampling" it with a d20, which has only twenty "5% chance sampling points" and on top of that some may mean something and some not.  For example some character might need only a 3 or more on the d20 while others might need a 19 or 20 to hit their target.  So what does a 12 mean?  Does it mean I moved a ton of air with my sword?  Does it mean I hit the target, but the armor was too strong?  Does it mean I was going to hit the target, but just on the last second he dodged?

My recommendation to D&D, keep those signals separate and sample them independently.  Have a real "to hit" roll.  Give characters the opportunity to parry, dodge or catch the arrows in a separate action.  Then face off the weapon vs the armor "mano a mano" and see what happens.  But if you keep mixing signals you'll end up with rules like these:

Dodge : + 1 dodge bonus against an opponent (no matter how many attacks the opponent has)
Deflect Arrows : Once per round you can try to deflect an arrow.

One adds a value to the die roll and applies to all opponents, the other can only be used once per round.  That type of inconsistencies and add-on rules drive me nuts.  Why not look at other games and see how they have actions and they can be used to attack or defend?  They each have bonuses for that action be it parry or dodge or catch or whatever.  You can dodge as many times as YOU, not your attacker has actions.  Dodge bonuses apply to your dodge roll.  You can deflect arrows as many times as you have actions, not an artificial once per round.

By keeping the actions separate: "to hit", "to evade hit" and then "to damage".  The events are easier to view and the game easier to balance.  More so since you haven't "mixed these signals" you have more detail in the attack, better story telling and less need for tables later on to sort out your "aliased signals".