Vulture Squadrons are 300pts each...............

LOL
I have seen this type of Army list before, and as has been stated above, Space Marines do have a pretty easy time of it against them. The Speed Freaks Army would run a close second to the Space Marines, with a mobile Chaos Marine Force running a close third.
Your activation count is on the low end of the scale with four out of seven formations that can be easily taken out of action due to low numbers. Most low activation armies are the reverse of this and are made up of a majority of large harder to break formations and maybe one or two small formations (Usually long ranged support formations whom remain well out of the action, hopefully)
As has been stated above my targets would be those Vultures and by turn two I will have taken at least two of them out of action. Then in turn three I would use the activation advantage to go after the Russ's in assaults.