Nova Driver vs. Arcana (LD-wise)

Arcana
Elemental damage
Faster bullets
Larger clip
Less damage per bullet
Knockback
Charge: Weak but has knockback
Nova Driver
Elemental damage
Slower bullets
Smaller clip
More damage per bullet
Ricochet
Charge: Powerful but no knockback
Stats show that both of these guns are to some extent balanced in their stats LD-wise.
What makes Arcana overused in LD and what makes Nova Driver underused in LD?
It's the range, bullet speed and extra bullet that makes it more useful in LD.
Typically people use guns for spacing and keeping pressure on people, so the slight reduction in damage isn't a big deal. It's more important to not be out of range or accidentally reload, and hit people moving away from you (drivers have trouble with this).
The charges are largely irrelevant because they're both high risk low reward compared to storm/hail driver or brandishes.
Nova only really beats out arcana when fighting 2 or more people at once or in closed spaces because the ricochets can get you extra damage.
Nova and drivers in general are more fun because there are certain tricks you can pull off (wall-shots, wall-charges, range boosts from charge ricochet, shooting behind forcefield etc etc), but arcana is more reliable.

We should also compare the Arcana and the Argent Peacemaker, and how the Arcana is also more popular by comparison.
The Argent Peacemaker has more shots than the Arcana, said shots travel even faster, and the former has the potential to do more damage in one clip than the latter. However, its faster firing rate is its downfall in LD, as the shots come up too fast one after another to give time for the enemy's inviciticks to wear off between each hit, allowing said inviciticks to absorb some of those shots and overall making the Argent Peacemaker weaker than the Arcana. It also doesn't help that the LD meta is much more focused in burst damage than damage-per-second, no thanks to some swords effectively taking half of your HP in one slice, so even if inviciticks were gone, the gun would have a hard time thriving there.
As such, the Arcana is the solid and effective middle ground between the Argent Peacemaker and the Nova Driver, it being fast enough for its shots to hit more consistently, with enough shots to give you some room for error, and with just enough damage to make it pretty powerful in the right hands.
In most people's eyes, it's a lot easier to hit people with Arcana than Nova because of Arcana's superior bullet speed and size, and not to mention ease of use with a 3 shot clip rather than a 2 shot clip that Nova has. Nova does have the potential to be more damaging and be more tricky (as in using ricochets in tight corridors and such), but you have to work quite a bit harder to actually hit people with it, than Arcana which is much easier. Plus, in general (not just PvP), Nova has a considerably steeper learning curve than Arcana, so it draws more people to the Arcana in the first place.