I asked this question about Observer pattern, so I could get some help with my talk that I have to hold. I understand the problematic part that its teasing a debate, but I tried really hard to phrase it in a way it does fit Q&A format, by specifying 2 things I want to know, so nobody would start a arguing. What can I improve there so it will not get closed? (I have another talk I have to hold in a month or so - and I would be really happy to get peoples support)
As mentioned in the FAQ, your questions should be about problems that you face that relate to software development. Putting together a presentation or discussion is not an aspect of professional software development, which makes the current wording off-topic. Phrasing your question to only gather opinions or thoughts is also not constructive.
However, the subject matter (in this example, design patterns) is on-topic. So if there's some aspect to the subject that you don't understand or need clarified, that would be acceptable to ask. In your example question, the problem is that you simply ask for suggestions - that's not a suitable question for a Q&A format.
I don't see how "I'm giving a talk, (details), any suggestions?" isn't a polling question ("polling" as stated in the section of the FAQ cited as the close reason"). A question asking if there are alternatives to the observer pattern other than polling still might get closed as a list question, but I personally probably wouldn't vote to close it.
One way is to separate it into multiple questions, the question itself has a ton of subquestions inside of it.