Just so you know, it’s harder to combo from a launcher in the corner since your partner has to run a longer distance. When I started, I always dropped my combos in the corner and wondered why. I thought it was an input drop bug but it’s just the longer running distance that makes the timing more strict.
Where you are on the screen also affects things like wall bounce combos and switch/cross cancels. So you need to be aware of that.
For post-launch combos, ideally you should avoid light normals as they deal weak damage and scale the combo down too much. When possible, use a heavy special cancellable normal (Christie has s.hp and c.hp) and cancel it into a combo ender (Stinger for Christie). If you play a character that doesn’t have a heavy cancellable normal, then use medium links into special. Only use something like 2 light normals to hit confirm at the beginning of a combo, but never in the middle or at the end.
I don’t know anything about Jack. And there’s a newbie thread btw.