I did some cursory research on the POE wiki, but I couldn't quite find the answers to these:

 

1. Are the accuracy bonuses conferred by the weapon feats (noble, ruffian, etc.) properly displayed in your character sheet? My rogue character should have had a bonus in daggers but not stilettos, but my accuracy ratings did not reflect that when wielding them both. I'm almost positive I've included all other relevant factors (the accuracy-boosting qualities of both weapons), but the numbers just aren't reflecting my weapon feats. It's possible that I'm just missing something obvious, but I wonder if anyone else noticed this.

 

2. What is it that gives a weapon the "unique" tag/yellow border? Do they always possess enchantments that you can't otherwise reproduce by crafting? Or are they simply prefab enchanted weapons of relatively good quality? I keep seeing these unique named weapons in shops being sold for exorbitant sums, and I can't tell if I'd be better off crafting a comparable weapon myself.

I think there is currently a display only issue with accuracy bonus (display is wrong but accuracy is properly given in combat)

 

No idea about #2

I did some cursory research on the POE wiki, but I couldn't quite find the answers to these:

 

1. Are the accuracy bonuses conferred by the weapon feats (noble, ruffian, etc.) properly displayed in your character sheet? My rogue character should have had a bonus in daggers but not stilettos, but my accuracy ratings did not reflect that when wielding them both. I'm almost positive I've included all other relevant factors (the accuracy-boosting qualities of both weapons), but the numbers just aren't reflecting my weapon feats. It's possible that I'm just missing something obvious, but I wonder if anyone else noticed this.

 

2. What is it that gives a weapon the "unique" tag/yellow border? Do they always possess enchantments that you can't otherwise reproduce by crafting? Or are they simply prefab enchanted weapons of relatively good quality? I keep seeing these unique named weapons in shops being sold for exorbitant sums, and I can't tell if I'd be better off crafting a comparable weapon myself.

1. It's a known bug. It only affects display not value and upon entering combat will revert to normal. It's fixed in the 2.02 beta if I recalled correctly.

 

2. It's complicated. There are purple "fine" items that have unique effects, namely the Engwaithan scepter you get from one of the Ondra's Gift quests; Also in Ondra's Gift you'll get into a "gentlemen's club (no, really)" where sell golden weapons that don't have unique effects (but they all look really cool). That's the only occasion where you can get gold weapons with normal stats.

 

Oh, and the last level of Od Nua.