People have indeed thought and played with this rule, the Chinese did that for thousands of years. It's called group tax: http://senseis.xmp.net/?GroupTax .

So this may have been thought of and talked about already but I have never heard of it. I suggest that a player ought to lose 2 points for each independent group he/she has on the board. Maybe you already know where I'm coming from with this and maybe you don't. Let me explain. It comes from what I consider to be the most simple and pure (quite subjective of course) scoring system: No-pass Go being one way where the game doesn't end until one player has no legal move. The other way is to say that the object of the game is to get the most stones on the board. Either way, think about this(and forget komi for now) If the game comes to what we generally consider to be the "end" (which is technically just the point at which no more productive moves are available and thus the game is counted up to see who's ahead) and Black has control of 181 intersections while white has the other 180, black would appear to have won without question. However, imagine that black has four separate living groups while white has one big connected group, if you play the game out completely, both players will fill in their entire territories until only the two eyes necessary for life are left vacant. However, black will reach this point having filled in 173 intersections (181-8) where as white would be able to fill in 178 (180-2). At this point, white has more stones on the board than black and black will not make another move or he will self-atari and be killed, losing by an even larger margin. Under no-pass rules, black will be forced to self-atari giving white the victory one again. I don't expect anyone to do anything with this or ever play this way, I just found it interesting and wondered what you all would think.

Why on earth is this not the standard way to play Go?

Because filling the board is extremely tedious.

Nonetheless, I don't quite understand three things: why it's the norm to play without group tax, why people like to keep score in such a way that doesn't account for points left in dame, and why Komi includes a half point...

Why on earth is this not the standard way to play Go?

- Every stone or group of stones must maintain one vacant liberty at all times in order to remain on the board (a player cannot end their turn while one of their own stones/groups remains without a vacant liberty).

you must be more precise: you can play a move removing the last liberty of one of your groups if by doing so you remove the last liberty of an opponent's group (in other words, you have to say in which order groups are removed).

It's just that after gaining a better understanding of the finer points and origins of the game we call Go, I want to better understand where these other sorts of counting methods and rule sets come into play. So territory scoring is said to simplify the game, how so?

To a new player learning the game, telling them that you lose two points for every separate group would sound like some additional rule that's added onto the game. However, with a better understanding of the core concept of the game, you realize it's just the proper way to deduce who will win the game without actually having to fill in the entire board as in the picture above.

- The player who is able to get the most stones on the board is deemed the winner (Like in the picture above, the game never actually ends, it just reaches a point where neither player wished to play another stone, and therefore the player who stands in the deficit is at that point declaring resignation.

At this point Black has the move but does not wish to play, even though he has one more stone on the board than White. (As it happens, White does not want to play, either; but I could have easily contrived a position where White would have had fewer stones on the board than Black but more plays.)

Your remark is very clear and I realise I misunderstood the previous post. Today I had another idea. If we allow another legal move which is giving back a prisoner to your opponent, does no-pass go becomes the same as most-stones go with group tax? (maybe disregarding some final ko situations)

Was there ever a ruleset allowing this? Of course it is inspired by the idea of pass stone.

No pass go with prisoner return yields territory scoring with a group tax. Professor Berlekamp demonstrated that over 20 years ago. As it turns out, the oldest existing game records that are scored seem to use territory scoring with a group tax.

Dames are small.

So even under that idea, wouldn't it be relevant whether the amount of dame left over at the end of the game is an even or odd number?