Great post. Generally, my idea is to bring back all the attributes plus map annotation, an enhanced version of Mark/Recall and to completely rework / de-linearise larger dungeons. But that would require Bethesda to be a "GOOD COMPANY".
As you said, the character level used for scaling should only be related to combat skills. No way around this: all other skills serve the purpose to get around combat situations. As a counterpart, dungeons should be designed with multiple paths in mind. Make sneaking a viable option and put enemies of varying levels within the same dungeon: have the part/path of a cave leading to the phattest lewt populated by stronger enemies, allowing to be bypassed only if you use high level non-combat skills: acrobatics, levitation, illusion, speechcraft (talk your way through a bandit blockade, WHY THE HELL NOT), sneaking and lockpicking, also why not add a skill to find secret passages.
That way if you're specialised enough you can still get the loot and that great feeling of circumventing enemies which are way stronger than you, through clever use of skills you raised otherwise. But that won't make you gain a level and become magically stronger. If you can't get through, you can still get as far as you can (usually, get to the intermediary and quest-related loot) and then when you're getting your ass handed back to you, just register the dungeon (annotation + fast travel back without breaking the lore through the use of that little thing called 'mark/recall') and come back later to get the high level loot.
Finally, low importance dungeons/camps should level otherwise normally if they "limit bandits to I don't know, level 30 and then replace them with complately different enemies instead of just Bandits on Steroids."
Yes.Leave a dozen "end-game" dungeons with "fuck your shit up" variety of enemies.
- Separate "combat level" leveling and skill levels, more varied skills.
- Filler dungeons or camps, scaling with the current player combat level with a few possible pre-configured difficulty settings (easy, medium, hard).
- Larger dungeons, scaling with the current player combat level with a few possible pre-configured difficulty settings (easy, medium, hard) and a path leading to high-level/unique loot with fixed-level enemies and ways to circumvent through skill use.
- Special dungeons with fixed-level only enemies and ways to circumvent through skill use.
This poses the problem of raising skills, which should probably be a mix of the skill-specific XP and a cap tied to the combat level and other skills.
As for the easy/medium/hard setting for difficulty scaling, find a way to communicate it to the player beforehand through hearsay or geography. A super secret hive lost in the mountains should be more difficult than a bandit camp in the open.