I would start by posting questions here on StackOverflow, describing your actual symptoms (one question per theorized bug, please), so we can hash out if indeed there is a compatibility issue. Or perhaps your problems have already been addressed here in other questions.
Once we have determined that there appears to be genuine flaw in a device, depending on the manufacturer, I can perhaps alert them about the problem. While there are few public channels for this sort of thing, I try to establish relationships with as many device manufacturers as possible, just for these kinds of issues.
Also, once the compatibility flaw is confirmed, I, you, or somebody can file a bug against the Compatibility Test Suite (CTS). This is a battery of tests that a device must pass to qualify for the Android Market and related apps from Google. Genuine compatibility problems should be picked up by the CTS, so we do not run into similar compatibility issues in the future. For example, here is a CTS bug I reported related to a flaw Samsung phones, and here is a CTS bug I reported related to a flaw in HTC phones.
It is fairly important that I see compatibility-related StackOverflow questions. Since I don't know if the @ syntax works in questions, you may wish to append a comment to your own question, addressed to @CommonsWare, to increase the odds that I'll find your question.