Currently, I have the Ash Tail Cap & Coat and the Dark Thorn Shield. I am willing to switch, but basically, I noticed that I can also get quite a bit of attack speed with the Vog Cub Cap/Coat and/or the Swiftstrike Buckler. The wiki seems to say that the bonuses increase by percentage or based on the base stat. Since the Dread Venom Striker has more speed than attack, I'd imagine it would get a better benefit out of more attack speed, but I'm unsure if more attack speed is better than more damage. It seems that a faster sword would benefit more from more attack speed, but I'm unsure.
Basically, are attack speed or damage bonuses (or even a balance of both) better for the Dread Venom Striker?
Years ago, the guild Lancer Knightz compiled detailed damage tables for a variety of ASI levels and damage bonus levels. Some of their damage tables are obsolete, but most of the swords haven't changed, and you can trust the DVS numbers.
The short version is: Each level of ASI increases DPS (damage per second) by about 3.6%. Each level of damage bonus increases DPS by about 5%. So you're generally better off increasing damage bonus.
There are many caveats. The DPS numbers assume that you are doing full combos, not "stopping short". They ignore poison. They are empirical relationships, fit after taking monster armor into account. ASI always helps a little, while damage bonus sometimes helps a lot (if it decreases the hits per kill) and sometimes helps not at all (if it doesn't). The DPS numbers don't say anything about the poor interrupting behavior of DVS compared to WHB. And so on.