I've taken a lot of party drugs...
MDMA, amphetamine, Dexedrine, ghb/gbl, cocaine, cannabis, 2C-I, DXM, 5-MEO-DMT, mephedrone, poppers, shrooms, LSD and several LSD analogues.
MDMA but never MDA specifically? Also, Dexedrine is just an isomer of amphetamine and I guess they're party drugs, though I tend to think of them more as productivity stimulants, as opposed to meth which is a recreational stimulant. In my experience, it's better if I keep dex/adderall/amp.sulfate as productivity tools and use meth for partying. But that's just me. I'm not so sure I would classify DXM or 5-MeO-DMT as a party drug but I'm just splitting hairs; and either way I take your meaning and have a sense of your drug experience from this.
Have done a lot of...
MDMA, Dexedrine, ghb/gbl, ketamine, mephedrone, poppers and LSD analogues.
The mention of mephedrone and previously of amphetamine (not methamphetamine) leads me to believe you're probably not in the US.
Whoa. Those are two of my personal favorites, but I'll bet you hear that a lot whenever you tell people this. I mean, different strokes for different folks and all that.
Cocaine has no effect on me.
Ummm, I'm not very inclined to believe this. I'm not at all saying you're lying – indeed, I think that you honestly believe cocaine has zero effect on you, but I think you're drawing conclusions without sufficient data. Have you tried various routes of administration? Have you had really good blow? Does it at least numb you gums?
Diacetylmorphine is boring and the drug is overrated. Ppl have just stupidly romanticized the idea of "Heroin" over the years, which was a brand name. Again: diacetylmorphine, just another opiate analgesic. No big whoop.
Why would you be scared to try crack cocaine if you think cocaine has zero effect on you. They are literally the same drug. Powder cocaine has a hydrochloric acid molecule attached to it so it becomes a water soluble drug salt you can snort and it will enter the blood. Otherwise, in base form, its melting point and boiling point are reduced thus facilitating vaporization. The high is pretty much identical, and rather lackluster, in my opinion.
Compared to LSD, its analogs, and many other drugs, yes, cocaine is oddly not very inebriating whilst being hella expensive. I mean, $20 worth of acid will fuck your world up, meanwhile $20 of coke ain't shit.
and crystal meth in case I like them too much.
Personally I love it. I use it recreationally mostly, not as a productivity stim, for which the primary amine, amphetamine, is better suited.
Fentanyl is best left to medical professionals. Not a good street drug. And then PCP is one of my favorite drugs of all time. It's very spiritual and meditative and deeply mind-altering. If your relatives don't have serious mental health problems, and you can get a trusted trip sitter, I say go for it. After all, you only live twice.