That's debatable. An F-15E going full burner 200 ft off the deck is not gonna be much easier to catch than an F-111. Plus, it has much better A/A capability than the Vark.
IIRC, the 111 is one of the few planes capable of supersonic flight at sea level. The F-15E is not.
A minimally loaded F-15E can break supersonic - IIRC it's max speed at sea level is ~800 kts, which is about Mach 1.2. Apart from bombs, the only thing that limits its low level speed is the AAQ-13 LANTIRN nav pod, which actually imposes a limit on how fast the Mudhen can go - I don't remember the speed at the moment. I know the ability to attain Mach 1.2 at low levels was a design requirement for the 'Vark, but I with a full loadout of 4 2000lb laser-guided bombs and the Pave Tack targeting pod, I doubt it'll be able to achieve that design requirement.