Gold adds weight
Your gold can be put in a bank for a letter of credit
Quests can be refused without lowering your reputation
Weapons need to be repaired by an armourer
I can see the other ones, but... really? Gold having
weight is one of the specific things you list as making Dagerfall great? Gold having WEIGHT?
Anyways, people think it's the best because it's really big and it has a lot of stuff. Well, kind of. The actual amount of content isn't THAT huge given how much of it is reused throughout the game, but it gives the
sense of being loaded with content whether or not that's actually the case. Besides that, it does a fairly good job of masking a lot of its issues, it is filled to the brim with atmosphere, and it frequently goes out of its way to convince you that you're in a real world and not just another game.
As a game, Daggerfall is mediocre at best and terrible at worst. It plays like crap, it's loaded with repetition, it's got tons of design flaws and unfinished content, and even what little variety there is seems to be drowning in a lack of real variation (the basic quests that the random generator plays Mad-Libs with to make the quests you actually do frequently borrow from
each other, to an even greater degree than Bethesda's more recent TES games). But the thing is that it distracts you from a lot of that when you actually play it by hiding some of the flaws and leading you away from others, and by the time you're done with it you'll generally feel that you had a good time with the game no matter how terrible it seems like it should have been.