I used to play a lot of this. I never really learned how to dual-wield properly or use guns, but I discovered that I was really good with flails. So i got myself a Steel Whip and a ruby gem and proceeded to breeze my way through about 40 arena levels.
Personally, I think flails are the best weapons in the game, once you learn how to use them. Because it's on a chain, it's much more flexible. You can switch directions in a second and hit from angles that would be impossible with any other weapon. The chain also makes it easier to start swinging and make short swings, since the other weapons are more fiddly. That flexibility combined with the power it has, means you can pull off some crazy stunts with it. The arena I was fighting in was guaranteed to get wrecked, as I smashed riders into walls, smashed them through the walls, smashed them into other riders, and even caught their bombs (hated them) and threw them back into their faces. I could never do any of that with the other weapons, and I always thought they were too fiddly. Also, there's nothing more satisfying than smashing someone into the wall so hard they die instantly. I would recommend turning down the sensitivity, if you want to do that.
Dual-wielding swords is kinda badass, though, and I kinda like the jackhammer move. Hadn't thought of using guns like that.
I might install it again, it was really fun.