VSX is not my specialty but I'll take a shot here.
As far as the high F2F, try applying IPS profile "Optimized" to your gateway and see if it improves the situation with high F2F. If it does not, try running these commands in your VS:
ips off
fwaccel stats -r
(wait 60 seconds)
fwaccel stats -s
ips on
Did F2F go way down in "fwaccel stats -s"? If so it is definitely something in your IPS profile config, probably an active signature with a performance rating of "Critical" handling a lot of traffic. Make sure you run "ips on" at the end!
If F2F is still stubbornly high you could have fragmentation or some other kind of issue interfering with SecureXL. Please post the output of the following command to this thread:
fwaccel stats -p
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