FO3's levelling scheme for opponents and loot was better than OB's, but it still suffered from the same problem with items and creatures not existing anywhere in the world until you reached a certain level, and then they were suddenly "common". In MW, almost everything existed at least SOMEWHERE in the game, regardless of your level. They became more frequently found, perhaps, but didn't go from "non-existent" to "common" overnight. Just as importantly, very little, if anything, in MW vanished after a certain level, as many things seemed to in OB. You could still buy an iron dagger from a merchant, but nobody else in the game world had them anymore, once your character progressed from that to steel and chain, dwarven and mithril, or glass and daedric. In MW, many of the armor types were usable and effective from the beginning until at least mid-game, since the differences in stats weren't quite as pronounced and the opponent levelling/scaling wasn't so radical as in OB.
Combat was "better looking" in OB, but relied far more on player skill than on character skill. In terms of control, OB introduced player-activated blocking, but took away 2 of the 3 attack forms, and reduced attack speed/strength from MW's variable amount to OB's "standard or power" attacks. The strength of an attack in MW was dependent on how long you held back and "charged" the strike, giving you the option to do quick jabs and slashes for less damage each, or wind up for a full swing, or anything in between. You could also do 3 different forms of attack, although sadly, one of them was almost always "better" than the others, rather than being better against specific forms of defense or armor. In OB, you just pushed the button and waited for the animation to play. I actually felt LESS in control of the character in OB than in MW.
To me, the most glaring and disturbing trend is the gradual "simplification" of the series by removing one thing after another. In terms of diversity of items, spells, skills, and factions, DF was better than MW, which in turn was much better than OB. One would think that as the game series progressed, things would be ADDED, not subtracted.
Fallout3 lacked high level content, a late character would be equipped with special weapons and be very skilled with them and have so much health he could only be killed if somebody blow up a car next to him.
Broken steel added high level content so it obviously did not exist before the addon, downside was that the new enemies was very hard to kill for an unprepared player like me.
Agree with you about Morrowind, however it also lacked high level content, the game tend to get harder around level 4-8 as stronger enemies get more common and you start going up north. At level 15 you are very hard to kill.
Don't think any monsters disappear in OB, they become less common but you still run into imps at level 30, yes it's exceptions the weaker stunned imps are gone. yes weapon and armor changed, mostly to keep the npc from being a joke as in Morrowind, equipment is just as important as skill in the game. Instead the leveled armor became a joke
My idea of weapon and armor repair condition might solve this.
Never got the point of attack types in Morrowind, if you had different attacks they should have different weak and strong points. Strong but take a long time and leaves your open, weak but bonus against armor.
I mostly see the things cut from Daggerfall to Morrowind as unnecessary features, mostly loads of pretty pointless skills. Other things people missed like houses and horses was back in Oblivion.
From Morrowind to Oblivion it was two sort of cuts, something was cut because of time restrains and because the devs thought they was secondary, spears and crossbows are most missed.
Other cuts was to balance the game, Morrowind is extremely unbalanced, not only alchemy, but cast on use magic items was overpowered, levitation was mostly used as an exploit. other things was to hard mostly that you had to sleep to regain mana, so mages had to fall back on alchemy abuse. Oblivion is far better balanced but they went to far.