I know Flight simulator since the release of version 1.0 in 1982
and I still continue today with the 2006 version - Flight Simulator X or the 10

I mainly fly with the Boeing 737 ng from IFLY cbe (Cockpit Builder Edition) The flight systems and dynamics have been tested by actual 737 NG pilots to ensure the correct performance and functions of the aircraft. real aircraft. The "Pro" disk allows you to easily configure gauges on multiple monitors and networked computers without having to run unanchored windows on a single FSX machine. This massively improves performance over running unanchored gauges on the FSX computer, and gives many additional benefits to the cockpit builder.

Rex4-Textures-Direct is a built-in global environment texture utility and effects add-on for Microsoft FSX, FSX: Steam and Prepar3D and is DX9, DX10 and DX11 compatible! Texture Direct takes advantage of new features in P3D while enhancing FSX to new heights.Designed for low and high end systems, the REX4 Texture Direct with Soft Clouds Enhanced Edition is comprised of over 17GB of hardware ranging from resolution standard to high definition choices. This package includes REX Soft Clouds integrated into the program. REX Soft Clouds is a new volumetric type soft cloud texture additive pack. This soft cloud pack gives a real volumetric feel to your clouds and brings an unmistakable touch of hyper realism to your flight simulator.

REX4 Weather Architect is a powerful weather generator / weather engine that allows you to create complete weather systems on a map with accuracy down to single latitude and longitude. Weather Architect is a one-of-a-kind weather creation utility, and unlike other weather engines on the market, it allows you to view, create, and completely immerse yourself in cutting-edge weather systems. Weather Architect gives complete control and creativity in developing detailed weather systems anywhere in the world, including over oceans, where no weather station exists in the simulator. Weather Architect works hand in hand with REX 4 Textures Directes and Soft Clouds to give you the most realistic experience possible

You can download a large part of Europe to fly over photoreal landscapes, go to this site click on the link below

On the RIKOOO.com site you will find very beautiful Photoreal scenes like here the Canary Islands in 2 parts and it's superb, also Corsica, great

On the Rikoooo site, also the United States

So for the USA, I recommend flyawaysimulation.com

SIOC is a powerful programming language, allowing to act on all the internal functions of Flight Simulator and P3D. You can download it from the Opencockpits website (downloads section)

So the best explanations on SIOC, you will find them on Claude Kieffer's site (in French)that's why I will not develop this subject, I could not do better I put the link below