Think the offsides are fine, just the time they take need fixing. Red card decisions seem okay but could be slightly improved.
The penalty calls are an absolute mess and need fixing ASAP. Just come to a collective decision as to what should and should not be a penalty, thats the ref on the pitch and the VAR. How you can have a system where if a ref doesn't give a foul the VAR team can go "Yep, no foul" and for the exact same incident if they gave a foul they'd go "Yep, foul". Hows anyone suppose to know what is and isn't a foul? Just make it consistent overall.