It sounds like you may have a few different complaints to attend to. At this stage, it doesn't sound like there would be a single quick fix cure for all that you have listed above or that they are related. As you know, fault finding is a process of elimination. It's best to tackle one fault at a time, then test after each change / adjustment / part replacement, to determine whether that change has made any difference / progress in solving that complaint.
As a start, I would suggest that you first follow the steps of advice in #6 above, before moving on to the next complaint. For us to try help you find a solution, you have to give us feedback on what steps you have done and if it was successful or not. Similar to your responce to the ignition park suggesstion.