Ratka Cernos makes a good gunning for the Dread's position of best bow. The Dread features innate red crit potential with just Point Strike and slash damage is the best of the IPS damages. However, to be really effective you need to use a Speed Trigger or Vile Acceleration mod. The Ratka doesn't need that, it frees up a mod space by having an amazingly low draw time. Plus, the Viral AOE proc and energy restoration are amazing bonuses. It's just a shame it's primarily impact damage, although to be honest you might not even notice unless you go really long. The Ratka also has the fastest flight speed of the projectile for bows.
The Paris Prime is no slouch in damage of course, but power creep has created two monstrous bows. A good Serration/Split Chamber/Point Strike/Vital Sense/Bladed Rounds/Elemental Combo while aiming for those sweet headshots will carry you just fine on the Dread, Cernos, and Paris Prime. The last slot is up to personal preference.
It is worth noting that the Daikyu is a viable choice of bow too. While not my personal choice because the draw time is
very long compared to the others and because you can't walk around with the bow drawn, it doesn't rely on the crit mods, doesn't have projectile drop, and opens up some interesting possibilities with it's exclusive Spring-Loaded Broadhead mod. That mod can beat out a 60% damage elemental mod AND the regular Bane mods. But that mod is conclave exclusive and I haven't been able to get my hands on it because conclave is terrible and trade chat doesn't seem to know it exists (or at least, that had been my experience when this mod became PVE available).
Yes I am one of those five forma Paris Prime nuts. IIRC it was my first Prime weapon.
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I am absolutely thrilled with how good Titania's Noble stance looks on my frames. I had been using Mesa Noble for almost everyone because of how slick the secondary weapon animations are, but Titania's definitely works amazing.
http://imgur.com/a/RpXN4
Might have to buy her Agile sometime. Edit: Used a not-ass resolution for the screenshots. Much better.