DXM with cannabis is synergistic but still doable, complementary taking the edge off the nausea smoothening it out while increasing the psychedelia that may otherwise stay too black and white with dxm.
LSD with K is like adding a catalyst on top of a catalyst, it's easy to quickly lose contact with reality and have just insane things happening sometimes with behavior to go with it. Most dissociatives can do that to psychedelics, but LSD is a pretty powerful psychedelic and K is very good at making you hole.
Definitely get acquainted with more doable trips, slowly trying more intense things but I think you have a way to go. Might wanna consider trying nitrous on LSD first since the combo peak of that is so much shorter.
I know a guy who came to from a LSD & K 'flash' drinking a glass of his own urine. There's plenty of trip reports on erowid to read... make sure you read the amazing glowing ones as well as the absolutely terrible ones for a fair scope. Cause again: there are only a few things I ever tried (like Salvia, some of my DMT trips) that can make a person lose it.
And if you really have a love/hate relationship freaking on stuff like that and doing it as almost a life style or reckless experimental period, I've seen way too high likelihoods of psychological scarring first and second hand. But if you go really easy and well prepared it can be done sort of responsibly I think, but a lot of rules apply like maybe a trip sitter etc, that a lot of experienced trippers don't consider a requirement anymore for their regular trips.