Classic Hornet is such a winner for a sim like this: plenty of countries operate them (US, Canada, Australia, Spain, Malaysia, Finland, Switzerland, Kuwait) and the performance data is easier to access. Super Hornet would be harder to do because of the AESA I'd think, plus the effects of LO and its other systems. Tomcat would be cool, but its gone and didn't have a lot of the new stuff like JHMCS
Plus only Australia and the US use the Rhino, and only the US and Iran use(d) the Tomcat.
They would be cool additions, but in my opinion not as good candidates as the Hornet. F-15 (even though Saudi doesn't really "operate" them) would be another good one in with those two, as for the Falcon, its been done to death!
Get the Hornet perfect first though I reckon, just my 2c
. Adding new, accurate jets is a lot of work.