Took 2 weeks to get the UAE residence permit, 3 days to change the embassy and got the interview letter in 25 days after that. The interview took place about 30 days after I received the interview letter.
I would like to disagree here. Yes, record keeping in Pakistan is bad but that does not mean all the people applying have faulty records. The vast majority of people applying for immigration are educated professionals and have their records in order.
As for giving the interview in English, your command over the language really has no bearing on whether you're eligible to immigrate or not. If you're not confident in speaking English, then yes, it makes sense to get a translator. But I'm not a native speaker or have any degrees in English and gave the interview in English and had no issues. Multiple people, even those not on the same speaking level as me, gave the interview in English and were approved easily. It is not productive to hold native speakers on a pedestal either. I know "native speakers" who are far below and also far above my speaking level as well. Everyone's speaking abilities are different and they are not dependent on the education system.
Immigration being a matter of security does not mean that the embassy has to give aspiring immigrants a hard time or look for reasons to deny, that literally goes against the entire concept of immigration and US immigration law. Yes, the onus is on the applicant to provide all their documents but then it is the embassy's responsibility to do background checks etc. to ensure that security rather than trying to trip up people in interviews with trick questions. No other embassy except Islamabad operates this way.
Some more productive advice would be: Try to not get nervous, the counselors are people just like you. Be confident during the interview, have your answers prepared beforehand no matter what language you're giving the interview in. Look up what questions are asked in immigration interviews and practice your answers with someone. Keep your answers in line with your main mandatory documents and any additional documents you are providing.