For other elements, one of the strongest controls I found was being excessively obsessive about the item level chart in the MIC. It isn't a perfect fix of course, but when individual treasure is in a dozen items rather than focused in 2-3 super-items per PC it gets rid of certain destructive optimizations.
Help me with this I don't fully follow.
Peace,
Necro
WBL in the DMG says a PC should have 2,700 gp by 3rd level, 5,400 gp by 4th level, and 9,000 gp by 5th level.
Given a chance, a non-caster is going to leap right for the magic weapon followed by armor with random enhancement, while the spellcaster will obsess about the stat boost item.
According to the MIC, a +1 weapon is a 6th level item, and +1
something armor or a +2 stat boost are 8th level items.
It scales up rapidly for other items, often to a peculiar degree. (A holy avenger is a 22nd level item, and thus epic, despite appearing in the DMG and considered almost "mandatory" for a paladin by 15th level or so.) A +6 stat boost item is 17th level, but could be "afforded" as early as 10th level, when even a +4 stat boost item should still be too much.
It can get even more abusive if PCs try to subvert some WBL concepts by avoiding consumables (potions, scrolls, and wands) like the plague, converting what should be regularly cycled WBL into more permanent items.
I saw this constantly in organized play, and it became a rather absurd task to challenge an over-optimized character, even when writers had access to material the players were barred from, when the PCs were pimped out with 2-3 "high level" items to the exclusion of lesser items that were simply irrelevant with that much optimization.
The whole thing is an artifact of the "Christmas Tree" Equipment Requirement in the design, combined with the poor differentiation of item levels in the DMG, and the regular subversion of WBL item placement in published products. (Check the commentary on the treasure in Vraath Keep in the RHoD sourcebook for an example.)
Altogether, players will "expect" items well beyond what the system expects as "balanced", but such items are so "kewl" even the designers and editors can't help but ignore their own rules.
And then you throw in crafting . . .