Err ... dueling does absolutely nothing if you use a shield ?!? Dueling only applies if you have a weapon in the main hand and nothing in the offhand ? It only words with pure onehanded weapons, too. If you equip a versatile weapon, it will use twohanded instead.
Works with Shield, hence one-handed Longsword is legit.
If still worried - use a Rapier, works out the same.
You suggest me take STR-based bardadin with sword and board? But how it will work with low DEX? I know about gloves that up it to 18 but in my imagination character with heavy armor< sword< shield and rogue-ish like gloves looks not very aesthetic. And did bardic spells are better than aura of hate of oathbreaker and improved smites?
The configuration I suggest does not use DEX for anything (except save throws). Aesthetics? That's purely up to you. Archery or Sleigh of Hand - use somebody else. As you seem to be runnign Team Evul! you should have the bloodsucker around for the latter.
I cannot comment on the Aura or Smiting. Well, besides the Spiteful something being handy in taking out foes difficult to hit otherwise.
