Why not switch out dark flare knight for buster bladder, dragon destroyer fusion? Negate dragon effects and prevent armed dragon effects. Plus larger boost for chazz dead dragons
the dragon destroyer swordsman must be summoned with BB or a sub and a dragon which sadly cant be subbed cause its a type not a specific name, but you could use slash dragon instead, you can equip BB and still have a 2600+ after vortex. you just need to watch out for his sets.
I'm using 2 Dark Magician, 1 Buster Blader, 1 Luster Dragon #2, 2 King of the Swamp, 2 Hex-Sealed as my fusion materials. Luster Dragon is a good 1 tribute that's searchable through Blue Dragon Summoner and opens up the possibility of Dragon Destroyer. It's been working great for me (past 3 Paladin farm events), I'd recommend it if you are already running Blue Dragon Summoner.
It's a backup, I've had my Paladin destroyed early game and that second one will keep my farm safe. It's unnecessary, but recommended if you have access to it. I wouldn't recommend spending gems just to get a second copy either.
The odds of him destroying a Dark Paladin are nearly zero. It'd require him to either open a hand of 2 Level Up!, Chthonian Blast and Armed LV3, you not negating his Level Up! or Lightning Vortex or for you to fail to Summon Dark Paladin for probably at least 2 turns. Or attacking into Chthonian Blast for no reason.
If he can turn 1 Armed Dragon LV 7, it's an automatic threat to Paladin, which is when I would need to attack into it or wait for his possible LV 10. Chthonian Blast would be the nuke in this scenario as mentioned above, leaving LV 10 as a possible future game ender. Once LV7 hits the board, it's too dangerous to leave unattended, so you have to hit it or risk a loss.