1. We've never seen the Borg _try_ to assimilate any of the Dominion species, so there's no evidence that they can't. In one of the DS9 novels the Borg fail to assimilate a Founder, but that's the only example to date that I'm aware of.
2. Since when do Dominion ships jam sensors? Please cite an episode or preferably a few episodes to support this claim.
3. We all know there's more to a ship than size...even if there was a Dominion ship bigger than a Borg ship that wouldn't mean anything in terms of power. The Krenim timeship was arguably the most powerful ship in all of Trek...if it fired at the Borg homeworld all of the Borg problems would be solved in one swift stroke.
4. Dominion phased polaron beams overwhelmed the Odyssey, but later shield designs were shown to withstand them.
5. Please cite examples proving that the Dominion can build ships faster than the Borg. In First Contact a Borg cube launches a sphere that, for all we know, didn't exist until 5 minutes prior to launch.
6. I would argue that Hawk's assimilation in First Contact occurred significantly faster than the Jem'hadar maturing in "The Abandoned."
7. Shelby speculated that a Borg cube would remain functional even if, what, 70%+ of it was destroyed? I doubt 10 attack fighters, even ramming a Borg cube, could inflict that much damage. And even if they could it's likely Borg shields could adapt to prevent the Jem'hadar from succeeding in ramming them.
Honestly, I'm not sure where you're getting the information for a lot of your allegations.