... Bother making a Xenon?

My friend is actually seriously depressed about the nerfs. It's saddening.

On topic:

I've decided that Xenon will be made, if for no other reason than to be a card mule.

My 3 card sets:

Kaiser/DrK/DS
Cannon/AB/Xenon (probably Mech over AB whenever I stop being lazy)
Mercedes/Phantom/Luminous

The third deck will be changed soon to:

Hayato/DA/Kanna

Are these condusive to a Demon Avenger's success?

Replace kaiser with Aran, that 40 str doesnt work with potential, so its not worth keeping in the long run.

Set 1: Aran/Hayato/DRK
Set 2: Mechanic, Xenon & Cannoneer
Set 3: DS/DA/Kanna

i think the best set would be

MM/Hayato/Kanna
Drk/DA/DS
Mercedes/Aran/mechanic

offers

4% crit/8% min crit, 8% boss damage, 8% max hp, 4% status resistance, -5% cooldown time, 10% chance to heal 8% max hp? 20% buff time
you get the warrior set as well

But then he wont get pirate set. 20% buff duration is from lvl 200 SS card, I dont think anyone would want to lvl 100 more lvls just for 5% longer buff duration. Same goes for all other values you listed, S is where people mostly stop, not SS.