LE and EE are not unrelated when you complain about armors being expensive, and what does "which are not very different to each other" mean? Are you saying that you think the protection that they offer should differ greatly in game...nevermind. OOO does not contain the "fix" you want, and that is it...
I am saying that the protection differs much less than you think, or than the developers intended, at low AR values, and much more at high AR values. LE and EE are entirely unrelated to this because i am not talking about armors being expensive as the problem - i am saying that mithril is barely better than chainmail, and that is the problem, not the cost.
If you refuse to listen, understand or see the problem, then it will be a fix that only i ask for. But does that mean there was no problem?
Here are the total AR values for various armors taken from the editor (stock oblivion, 50% boost from light armor master perk not applied, since that is an end game perk)
Fur = 16 AR (84/100 damage dealt)
Leather = 25 AR (75/100 damage dealt)
Chainmail = 30 AR (70/100 damage dealt)
Mithril = 35 AR (65/100 damage dealt)
Glass = 50 AR (50/100 damage dealt)
Iron = 40 AR (60/100 damage dealt)
Steel = 45 AR (55/100 damage dealt)
Orcish = 55 AR (45/100 damage dealt)
Ebony = 60 AR (40/100 damage dealt)
Daedric = 75 AR (25/100 damage dealt)
Essentially the problem is that if i add 25 AR to 0, i reduce damage by 25/100, as i do if i add 25 AR to 50 AR. But the percentage change in damage suffered is much greater, as in one cases the damage is reduced by 25%, where in the other it is reduced by 50%, That means you cannot balance armors in the high AR ranges the same way you do those in the lower AR ranges, but Bethesda does, with the same range between them and general increases of 5 AR between both light and heavy armors. This produces drastically different results
Assuming 200 health and 50 damage per hit, this is the number of hits needed to kill your character
No Armor = 4 hits
Fur = 4.7
Leather = 5.3
Chainmail = 5.7
Mithril = 6.1
Glass = 8
Iron = 6.6
Steel = 7.2
Orcish = 8.8
Ebony = 10
Daedric = 16
Note in particular that the range is 35 with heavy armors and 34 with light armors - almost the same range - but most of the light armors show little to no real difference (Fur 4.7 hits -> Mithril 6.1 hits = 30% more hits needed) while most of the heavy armors show a moderate difference (Iron 6.6 hits -> Ebony 10 hits = 51% more hits). Note also that Daedric is twice as good as Glass, despite only a 50% increase in AR (50->75 AR). Overall, despite a similar AR range, the difference is 70% more hits needed from fur->glass, while its 142% more hits needed from iron->daedric. Moreover however, from Fur->Mithril there is almost no point in upgrading except for aesthetics, while heavy armors enjoy an excellent progression.
Now lets see how many hits it takes when we assume our character is lower level, and the AR is halved;
No armor = 4
Fur = 4.3
Leather = 4.5
Chainmail = 4.7
Mithril = 4.8
Glass = 5.3
Iron = 5
Steel = 5.1
Orcish = 5.5
Ebony = 5.7
Daedric = 6.4
As you can see, with AR's halved the reduction in effectiveness is not linear, but much more drastic. What does this mean? It means that without armor our character will take 4 hits, with fur->mithril 5 will kill them, with glass->ebony 6 will be enough, and only daedric will allow this character to take 7 hits. For our character, Daedric is not even twice as good as no armor.
The point where armors really start to make a difference is 30-40 AR, which is what Ebony and daedric are around when used by lower level characters. It basically means that for lower level characters light armors fur->mithril are almost pointless, with only cosmetic differences, and all heavy armors or glass, except daedric, are only slightly better than no armor at all. Only daedric provides a decent boost (for a massive weight drag). Armors thus only start to come into their own at higher levels and AR numbers over 30-40, but by that point the player will generally have upper echelon armors rendering the rest obsolete.