Method of Salaah

Q: After your fardh salaah with jamaat, is it better for the Imaam to make dua loudly or softly and what's the best duas to read?

Q: What are the best duas to read in qaumah and jalsah?

Q: After reciting Surah Ikhlaas in salaah, I mistakenly said sadaqallahul azeem. Is my salaah valid or is there sajdah sahw?

Q: Is it sunnat to say Allahu Akbar after the salaam of a fardh namaaz?

Q: Is it sunnat to make dua after fardh salaat and a hadith supporting it if it's true. Many of my friends tell me that's an Indian innovation and not a sunnat of Nabi (sallallahu alaihi wasallam). Please advise. 

Q: When you want to read a big surah in salaah, but not in full. Is it okay to read from anywhere in the surah and stop anywhere? And can you read one part of a surah in the first rakaat, the part after that in the second rakaat? Or do you have to read different surahs in each rakaat? 

Q: In sunnah and fard salaah, what duas can I read in sajdah?

Further, in nafil salah, can I make dua in English in sajdah?

Q: My question is that it is compulsory, mandatory to make dua (rabbiq firlee) in between the 2 sujoods because every time I offer salah I don't make the dua (rabbiq firlee) in between 2 sujoods.

What is the hanafi maslaq about this? They say it is better not make any dua in between 2 sujoods. Please explain this issue

Q: How does one know when to repeat salah if a mispronunciation occurs, e.g. does pronouncing ملحق at the end of dua e qunoot as ملهق, require one to repeat? I.e. Using smalll haa instead of big haa.

Q:

1. Should a muqtadee say the takbeers when moving with the imam or straight after the imam, if he did so after the imam would the salaah be valid?

2. Should the muqtadee say the tasmee and tahmid or only the tahmid? If he did both would the salaah be valid?