Some monsters just disappear when you go up levels, and others just don't show up until you get more powerful. And don't get me started on all the bandits in glass armor, and marauders in daedric. There should be a small chance to get a good item at low levels. As it is, boss chests can be... well, disappointing to say the least.
You're referring to several different things in each sentence here.
Here is how Oblivion works:
Loot Leveling - controls when loot appears.
Enemy Leveling - controls when enemies appear.
Loot Scaling - controls the strength of loot once it has appeared.
Enemy Scaling - controls the strength of enemies once they have appeared.
I think things should be more random overall, so that people who really like the game can have more exciting replays. More hand placed items, put in weird or out of the way places.
This is a contradiction. You would like the game to be more random but you would also like hand-placed loot.
I agree with you about hand-placed loot adding to the fun of exploring, though. Oblivion's leveled loot eventually killed much of my enjoyment in the game. I stopped playing for a couple of months until mods began to add hand-placed loot.
Encounters should be more random. I'm not fond of spawn points. Too predictable.
Ironically, spawn points were invented to simulate randomization.
There has to be a way for developers to specify exactly where an enemy appears in the game world and where enemy cannot appear - otherwise the world would be chaos. Currently they have two methods of doing this: they can place the enemy by hand or they can add the enemy via a spawn point.
If they place the enemy by hand that enemy's starting position is static and its level is either static or scaled. It cannot be leveled: that is, if you place a wolf in that spot by hand there will always be a wolf there. And it will always be the same level wolf too, unless the developer scales it.
If they place the enemy via spawn points the developer gains a potential random effect. The spawn point can then be controlled by leveled lists, which determine which enemies appear at that spawn point. The leveled list can also specify what level the enemy will be. There is no need for scaling with this system.
I think perhaps what you mean to say is that there should be a greater 'chance of none' built into leveled lists. A developer is able to specify the percentage chance that nothing at all will appear at a given spawn point. The effect of this, in game, would be similar to removing that spawn point for a brief time. Every so often, based on the percentage specified and a dice roll executed by the game, nothing would spawn at that point when the player entered the cell. That would go a long way toward making spawn points feel a bit more random.
lvl 43 goblins are COMPLETELY OVERPOWERED.
Goblin levels are static Oblivion. Goblins, Goblin Ambushers, Goblin Berserkers and Goblin Skirmishers (which account for the vast majority of Goblin encounters in the game) are not scaled to player level.
In fact, there is not nearly as much scaling in Oblivion as many people think. There is no such thing as a level 50 Wolf, for instance. The percentage of enemies that are scaled in vanilla Oblivion is actual quite small.