I'm honestly jealous of people who report such strong effects from kratom. It does help to reduce opiate cravings but it's an extremely mild and short lived high for me even if I take like 10g. And to give a frame of reference, I can take 200mg codeine and it will feel much stronger than 10g kratom, so it's not like I have a sky high tolerance over here.
I usually get red strains for the calming effect but I also have tried green, white, and mixes. Some strains are stronger than others but even the strongest kratom I've had is about the same level as codeine.
Extracts obviously provide the strongest high, and I'd put the extracts at somewhere between codeine and morphine, but regular old kratom powder is weak as shit in my experience.
Probably the reason i get more kratom effects than you is because with the exceptions of the 5 surgeries i had where i jacket up my knees, wrist and neck from doing brazilian jiu-jitsu, i have otherwise never used opioids harder than kratom.
Sure, those times i did several times use high enough doses of oxy or hydro to get enjoyment but only for such short periods of time and then purposely did not ever seek them out on the street cause i know how bad that can be and i never will.
Other than that, i've only used kratom extracts and codeine a few times and all of my opioid experience other than that is from plain leaf kratom so that is probably why i never built the tolerance you have, and yet STILL, my kratom euphoria is nothing like it used to be when i started years ago and i will usually need 12 grams or so for a good high, but then it often isn't as good as i want and if i go higher it won't feel any better, BUT, i still get plenty of enjoyment out of it.
That being said, i've been off it for 8 days and i'm going on naltrexone tomorrow to help me to take a long break from both alcohol and kratom cause i need it.
I mean, i don't believe kratom is that bad for you, but it kills my drive to exercise and do certain things i need to do, and alcohol is obviously not the healthiest, and i need a long break and with how hard it is for me to moderate i can't think of a more effective way than a drug that stops me if i choose to take it, and then if i want to be able to drink or use kratom i can just stop and go back on, but i still plan on making it a good long while sober.