Although I love swiftstrike and use it as much as possible, there are times I switch to the more defensive shields, such as Owlite. As I've said to others before, you don't need to shield if you don't get hit. :) That's why I use swiftstrike even in tier 3. As was said here, you shouldn't get hit unless there was lag or maybe teammates sending enemies like lumbers in mid attack flying at you. Those will be the times when shielding would've been nice. Most of the time, if you're skilled enough, you can dodge everything, even in T3, in which case, use swiftstrike forever, but only if you're good enough.

I'm in the camp that prefers speed over damage increases. To me, speed increases are always effective. You swing faster and can kill enemies a bit quicker. If you have a damage bonus, you often still have to attack just as many times to kill the enemy, thereby negating any improvement for having a damage bonus, even in full skolver. There is a point when you'll be killing enemies in one less hit, but that point comes and goes quickly, as you'll just cross over to the point where you have to hit 3 times a little later than someone without the same damage bonus. With attack speed bonus, you are always faster, on the whole, plus being able to shield a tad sooner is nice. You'll also get to that all important interrupt swing faster.

In the end, regardless of what people tell you, you should go for what you think feels better, even if you can't prove which has higher DPS. I can feel attack speed bonuses. I don't often feel stronger with a damage bonus unless it's at that point where I'm crossing over from 2 hits to 3 hits, and that only makes me feel weaker since enemies are getting stronger.

Also, since this thread is called "Khorovod," I might suggest you move onto the sealed sword line. I loved using the Khorovod, but eventually its damage peaks early in T3. Not everything is about DPS, but when you're doing almost twice the damage in later T3 with a Divine Avenger or Gran Faust than you are with a Khorovod (taking into mind special damages vs the Khorovod's normal damage), you start to feel the Khorovod just doesn't cut it anymore.