Personally, I really enjoy the random challenge of awkward boss finds. Makes strategy a matter of execution and flexibility as well as just planning. It's really rare that something's too hard because of RNG rather than because I did the wrong thing.
Weak items: Mage plate, I thought the ward and orb were weak but apparently they're great for their conversion, the bloody sigil is probably good for the same reason, crystal ball?, hero's helm? blacksmith sword and shield? I don't know, what do people put in their veto slots? What items do people deliberately avoid unlocking? It's not so much that any particular item is weak it's that the optimal way to play might be to deliberately avoid unlocks and that you can't change your veto slots freely so you'lre always gonna have a stronger overall power level if you unlock items that work with a few classes and stick to those classes.
Orcs are stronger than humans right? A weak item could be replaced with an attack power item near the level of dwarven gauntlets and the +2dmg sword blacksmith prep could be made small. Also does anyone use the shield? I only use it on sorcerers. It could be made small too.
All of those items are really good. Mage Plate is specific to spellcasters and great on Assassins but it's probably an item that you'll either want or won't want. Ward and Orb both glorious for conversion and just really useful to have around. Bloody Sigil is good for same reason. Plus at low levels in general. Crystal Ball is one of the most powerful items in the game. It can win runs single-handedly. Hero's Helm's alright but it's rarely *the* thing you need.
Orcs vs Humans depends on A) class, B) level. Blacksmith sword's actually pretty good. Shield I don't use loads but it's alright for EM Paladins, Platemail stackers, old-school style vampiring and so on.
Currently the most rarely useful shop item in my view is the Venom Dagger. And even that's good on Gorgons or resist-stackers. Rock Heart is so case-specific that if you want maximum power you'd probably have it both veto'd and lockers. Tower Shield's rarely my item of choice.