I was wondering if an Unchained rogue with the Knife Master and Scout archetypes bumps all their feats into being better with wielding and throwing daggers and gets a custom made Large Dagger (which would be 1d6, 19-20, with a -2 to hit) would their throwing and melee attack to hit be reduced by just the -2 for wielding a large weapon? Is there a feat to take to negate the large weapon penalty? I envision a character with large magical returning daggers throwing them at the start of combat and then flanking when the tank gets in place to get the added dagger sneak attack dice the archetypes provide.
At 1st level, a rogue gains Weapon Finesse as a bonus feat. In addition, starting at 3rd level, she can select any one type of weapon that can be used with Weapon Finesse (such as rapiers or daggers). Once this choice is made, it cannot be changed. Whenever she makes a successful melee attack with the selected weapon, she adds her Dexterity modifier instead of her Strength modifier to the damage roll. If any effect would prevent the rogue from adding her Strength modifier to the damage roll, she does not add her Dexterity modifier. The rogue can select a second weapon at 11th level and a third at 19th level.
Weapon finesse
Benefit: With a light weapon, elven curve blade, rapier, whip, or spiked chain made for a creature of your size category, you may use your Dexterity modifier instead of your Strength modifier on attack rolls. If you carry a shield, its armor check penalty applies to your attack rolls.
Special: Natural weapons are considered light weapons.
you would lose your dex to damage using a large dagger.
I was wondering if an Unchained rogue with the Knife Master and Scout archetypes bumps all their feats into being better with wielding and throwing daggers and gets a custom made Large Dagger (which would be 1d6, 19-20, with a -2 to hit) would their throwing and melee attack to hit be reduced by just the -2 for wielding a large weapon? Is there a feat to take to negate the large weapon penalty? I envision a character with large magical returning daggers throwing them at the start of combat and then flanking when the tank gets in place to get the added dagger sneak attack dice the archetypes provide.
Even without losing your finesse training, this is a bad idea.
-2 to hit in order to get an extra 1 point of damage is a terrible trade-off to me particularly when you're doing significant amounts of sneak attack damage. That's 10% of your damage you'd be missing out on in order to get an extra 1 point of damage per attack. Even at 3rd level, that's probably 1d4+2d8+6 points of damage (assuming dex of 20 and a +1 weapon). That's an average of 17.5 points of damage. A -2 to hit loses out on an average of 1.75 points of damage per hit so you're WAY behind.