The ballistics computer in the aircraft is old and limited. If I understand correctly, it only supports ballistic calculations for two type of weaponry (not including cannon and AAM).
IIRC it's possible to hang some "extra" ordnance but you could only use it in CETKA mode.
Different rocket types have different launch orders, for example some are fired inner pylons to outer pylons and some other rocket types might be conflicting with that order.
The control stick basically has a switch that lets you use the A2G trigger either for bombs or rockets.
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