I'm going to be posting all the ideas I can think of (or some I've seen from others, I will point these out!) for the improvement of weapons like the Iron Slug, Sudaruska, Irontech Destroyer, and such. If I included an idea I saw from someone else, I'll say "someone suggested" it; say you did if you did, and point to your thread if possible.

THE BLUNTED BLADES
Spur/Arc Razor/Winmillion: You saw it coming. We need the 5* version of Spur. In fact, there's a whole thread on voting for its name. I think Winfinity and Quixote's Bane, among others, were good ideas for names. Everyone agrees there SHOULD be a 5* Winmillion. The only 5*-lacking weapon I approve of is Sunshards, and... well, that's Sunshards.
Troika/Kamarin/Khorovod/Sudaruska: Wielding this sword is about as safe as Russian Roulette (ba-dum, kssh) with its slow speed, and it is still outdone by DA and GF. I agree with a suggestion by another player: make Sudaruska at least a viable choice by bolstering the damage to be on par with Sealed Swords' DPS against neutral enemies. As for the charge, a small area wave that causes no damage, but knocks away enemies, next to the Sudaruska when it lands would be much appreciated. It could turn into a player-killing Leviathan, but the wave could interrupt (if not cause damage) and we've got Levi already, don't we?
Troika/Grintovec/Jalovec/Triglav: The main problem with Triglav is the freeze effect negating the knockback. Solution? Make the freeze take effect after the knockback. We don't need to hurt Graviton by having freeze NEVER negate knockback, just on the Triglav. Otherwise, everything that I said about Sudaruska applies to Triglav.
Cautery Sword: Someone suggested higher star versions of this, including a 5* Operator that causes Fire. I would not be opposed to this. Also, I'd give it explosions, if it gets buffed.
Rigadoon and Flamberge series: A little more likely on the status effect and we'll be good, Rigadoon and Flamberge aren't as badly unbalanced as Spur.

THE AIMLESS GUNS
Pepperbox series: The bugfix hurt. However, more fire always solves the problem! Also, extra damage, so it could be viable over Blitz/Plague Needle for neutral enemies? And please get rid of knockback, PLEASE. Poor Pepperbox just can't take it anymore.
Blaster/Valiance: I honestly thought of this series as based on the Mega Man buster, because of the three shots and larger charge shot... perhaps the charged Blaster shots can rip through enemies unhindered like Mega Man's own peacemaker? It would damage once, maybe twice, and continue on until it hit a shield or the end of its range. Not only would it be unique... IT'D BE REALLY REALLY COOL. They'd have to try not to make Valiance a GAME BREAKER if they did this.
Supernova: I suppose a little extra damage wouldn't hurt, since Polaris does have Shock. I never really used both Supernova and Polaris, so I can't tell you how I'd balance it.
Catalyzer series: Biohazard doesn't need a fix at all. I can solo JK easily with the Virulent Catalyzer. However, like Supernova, Neutralizer could use a damage boost. As for the charge... someone suggested a mist be left after each standard Catalyzer bullet (from either catalyzer) that normally does nothing, but sets off Catalyzer charges. Should make surrounded enemies go boom with less trouble.
Iron Slug: Oops, forgot this one at first! Iron Slug SAYS it has splash damage, but the splash is the same as Callahan. Fix this, it needs more splash, maybe on par with the Pulsars. Splash and knockdown = good.

THE BURNED OUT BOMBS
Haze Bomb: A longer stun would help. How does anyone subdue a dangerous species in four seconds? The other mist bombs are fine, even Venom Veiler (try it on a T3 Mender's healing rune, mwahahahaha).
Deconstructor: A bright spark in Bomb Suggestions 2 said, "Make it Elemental". I agree. It's a gremlin weapon (of which most are elemental) and was meant to kill constructs (weak to elemental). Problem?
Ionized Salt Bomb: Let's face it, nobody wants a Flourish with Slime Very High any more than a Flourish with nothing. Make ISB pure normal, and CUT THAT DANG CHARGE TIME DOWN. Maybe not as fast as Sunshards, but certainly quicker than it is now... perhaps the Charge Time of a Haze Bomb?
Big Angry Bomb: And why's he so angry? Because you slow down so much when you're charging him. A lighter, but not removed, slowdown, combined with a slightly bigger blast radius, will give Nitro a run for its money when you're soloing.
Irontech Destroyer: Someone suggested this be thrown like a grenade, rather than just dropped, after it's charged, and then light and explode like a normal bomb. This idea, plus attack interruption and a lighter slowdown, could put Irontech into its own field. A good idea would for it to cause minor Stun when it hits an enemy, like a Gremlin Demo's bomb throw.
Graviton and Electron bombs: Are not damage bombs on their own, but... have you seen the videos of Graviton sync'd with a charged Brandish or heavy sword? Maybe an FOV or Cold Iron Vanquisher would work... or a Pulsar... or another bomb like FV or Nitro or even BAB... or a Curse vial... the list is endless. If you play with someone else you know IRL, this is more powerful than you think, and needs no fix.

Questions? Compliments? Scathing rebukes?