Get ready to mod IL-2

Three paths: VP-Modpack, B.A.T. or DIY (Dod It Yourself).
First know you can have as many instances of IL-2 as you want and therefore you can have VP-Modpack, B.A.T. and DIY/Other. That C:/Games/IL-2/ folder you have? Go ahead and duplicate it if you like:.
C:/Games/IL-2 VP-Modpack/
C:/Games/IL-2 BAT/
C:/Games/IL-2 Other/
VP-Modpack, with its "less is more" approach, is a good starting point. It has not been updated in long time but it is stable, it works very well and should cover most of your WW2 needs, including PTO. VP-Modpack's
JETWAR Addon will take you to Korea and Vietnam.
B.A.T. is the largest super-mod ever assembled. Get BAT and you will have absolutely everything this game has to offer: WW1, Interwar period, WW2, Korea, Vietnam, Modern Ops... Mind you, BAT is huge: once you install BAT+Expansions your IL-2 folder will weight ~100GB.
DIY: Install one mod at a time. Time consuming and sometimes a frustrating experience. If you are interested in a few modifications only, then this is your way.
Make up your mind and let us know where you want to go next.
Cheers!