I've already given up on Arsenal as a Super because the lack of Ammo Melee makes X-linking and full attacks with Arsenal Melee weapons unsustainable, significantly reducing options. There are a few Brutal Ammo Ranged but they tend to be Heavy or extremely inferior to Super Builtin options. Overall I'm doubling down on maneuvers crossed over with Zero Weapon, Special Attack, Favored Maneuver, and Attacker/Predict. I keep a low-arsenal-space Defensive weapon on hand to maintain Attacker/Predict with multiple enemies as I go. Strike for early on when the buffs aren't stacked so it's hard to hit reals, Yell to get buffs early. Love or Battle Cry for important attacks. We'll see over the next level or so how that keeps up with the real-based party members.
One hilarious thing I thought of is the Steel Knife* Stack. Take as many X-linked Steel Knives as possible. Stack damage buffs. Since damage buffs are per attack and X-linked weapons each make individual attacks, all damage buffs are multiplied by your Arsenal level - 1 (including things like the bonus from str mod). At Attacker 1 at level 13, that's already a total buff of 36 damage. The downside is each one has to overcome DR on its own, but that's a LOT of chances to get 20s. (I'm not actually at 13 yet, just thinking ahead to possible hilarity). At arsenal VI at level 19, each level of Attacker alone gains you 75 damage, allowing you to potentially deal more average damage than some Arsenal VII Heavy weapons when using a maneuver that overcomes DR, like Colossal Strike.
The easy way to patch this, if you want to, is to say that when using Twin- and X-linked weapons any damage buffs and other damage bonuses are distributed evenly over all the attacks (or in some other way impaired).
* This also works with Assault Blade, but that's not Defensive. Going from Xd8 to Xd10 isn't worth it, and I prefer the wider crit range of Steel Knife to the higher multiplier of Assault Blade, especially when combined with Battle Cry or similar.