Just sharing some thoughts I have about Aerofly FS 4 (and FS 2) as pertains to glider thermal soaring.
Below are some screenshots of glider thermal soaring while in a thermal in MS FSX:SE using the CumulusX! freeware addon by Peter Lurkens. I really wish that such an external addon were available for Aerofly FS 4 but I suspect that the IPACS network interface does not support this capability otherwise we would be already be able to use Little NavMap for FS2 and FS 4 which we cannot because the IPACS network interface does not support this kind of network communication functionality for the general public to use. Right now the thermal soaring is pretty bad in both FS 2 and FS 4, being slightly better in FS 4 given there are more randomly generated thermals, but personally I find it to be impossible to stay centered in a thermal even if I, by pure chance, fly into one, both because there is no visual cueing and because the diameter of the lift zone seems to be very small even with maximum set on the thermals slider.
CENTERED IN A CUMULUSX! GENERATED THERMAL FLYING AROUND EDWARDS AFB (KEDW) CALIFORNIA, USA IN FSX:SE USING THE DEFAULT FSX:SE DG 808S GLIDER
Note: In FSX the default thermals are disabled, also no default clouds or wind, local temp set to 89 deg F from ground to 8000 feet in the month of May (Spring), time set to 2:00 PM local, blue sky thermal clouds enabled in CumulusX! addons menu so visible clouds are generated which are tied to the bluesky thermals with both being generated externally by CumulusX! and then being injected into FSX along with the cloud ground shadows. This was for done for the purpose of capturing the example screenshots. Normally if you set the right FSX weather conditions (cumulus clouds density and altitude ranges, no cirrus clouds, time of day and temperature altitude ranges) CumulusX! will use this data from FSX (via the FSX network interface data communication) to generate its thermals and own clouds and cloud shadows then inject the data into the FSX flight simulation engine so they can affect the aircraft and in-flight 3D scenery.
Ideally, if wishes were fishes, IPACS would arrange to work with Mr. Luerkens to make the Aerofly FS netcode interface be able to support an Aerofly FS 4 version of his CumulusX! addon.
Here are the settings I used in CumulusX! to generate the pretty easy thermal conditions that I used for the screenshots I took. KEDW elevation is 2,303 feet.