Destroyers are absolutely better than Afflictors, even putting Destroyers in a worst-case position (capped attack) and Afflictors in best-case position (+7% KA rate is active 100% of the time, which isn't possible given that they're an additional effect proc), even allowing for full Tantra +2 so that you get the higher damage kicks. Destroyers are still about 4% ahead in overall DOT. There is absolutely never a reason to recommend Afflictors over -any- other H2H weapon unless you're recommending in terms of looks and not damage. I'd take Wagh Baghs or NQ Hades over Afflictors.
Regarding the haste cap: To be precise, the cap is 256/1024, which in decimal form is in fact 25%. However gear with % listings actually gives some /1024 fraction to be added up, not the actual percentage listed. At present, the closest you can get to the 256 cap without going over (as far as I know) is from Tantra +2 head/legs + Black Belt. Their haste will be 71/1024, 61/1024, and 122/1024, for a total of 254/1024, just 2 shy of the 256 cap. By comparison, full Usu + Black Belt gives a total of 252/1024, 4 shy of the cap. Both of those combos appear to be "25%" according to the items' game text, and you'd need to add something else to put you at 26%+ 'listed' gear haste to actually hit the 256 cap.
Re: Mods vs +Attack -- +attack is actually still a very solid option even for weaponskills like Howling Fist/Tornado Kick. It's not common to actually hit the attack cap, so OKote vs Alky's can end up being almost the same, and in many of my comparisons Shura body beats Kirin's Osode. Also, if you're going well over the attack cap with Boost, you can drop Boost to increase your speed, in which case the +attack is still useful.
Regarding OA2-3 Footwork vs standard with, for example fire path Taipan Fangs +1, it depends on your gear set. Excluding Relic/Mythic/Emyrean:
Full Tantra +2 using OA2-3 Footwork is the best.
Next is Taipan +1 with full Tantra +2.
Next is Taipan +1 with full Usu.
Next if OA2-3 Footwork with Poise and mostly Usu build.
And then you fall down to the lvl 80 weapons with full Usu.
Store TP tiers for Footwork:
+10 Store TP gives you a 7-hit (2 weaponskill hits, 5 melee hits). This is doable with a few common items.
+29 Store TP gives you a 6-hit (2 weaponskill hits, 4 melee hits). This is doable with /sam or Sam Roll.
+54 Store TP gives you a 5-hit (2 weaponskill hits, 3 melee hits). This is doable with /sam + Sam Roll with a sam in party. Generally impractical.
May need to adjust the numbers slightly if you want to be able to change out gear that has Store TP on it during weaponskills.