As I said, not with Hydromorphone, but mainly with Codeine and Dihydrocodeine. I would have preferred Morphine, Oxycodone oder Fentanyl but in Germany it's hard to find reliable sources and at that time I took Meth I had no other. Well, Cod or DHC do also.
I tried Meth stand-alone, but found it simply too stressing, it was partly uncomfortable. The Opioid didn't just calm me down a bit, it comes forward with inducing an additional euphoria merging with that of the Meth. The result was comfortable. Keeping the opioid-level constant smoothened the usually very uncomfortable feeling when Meth-effect comes to an end. But I was careful enough not to wind up doses too much.
Hydromorphone is no such strong antitussive than Hydrocodone. And it depends on what causes the cough. It will be have suppressing effects, but sometimes a product with herbal ingredients have supporting effects.
The Hydromorphone will not have any effects on the Dopamine-rush I would describe as obstructive. It's likely a bit softer/smoother. I like that!
I'm not a specialist for high-dose-use and I would avoid that! Not just because of the pure acute-physical danger of cardiovascular problems, hyperthermia, convulsion, stroke and other things that can cause sudden deatch, but because of the neurotoxicity - Methamphetamine is known for causing axonal degeneration with long-lasting reductions of the levels of Dopamine and Serotonin. This axonal damage seem to depend to core-temperature (the higher the temperature the more severe the damage). Higher doses are suggested to cause more long-lasting damage (prolonged anhedonia, parkinson's diease, cognitive impairments, ...). I did not take it very often and even so I was very careful. One should always think about if it's worth the fun. You are aware?