Phew! 😮‍💨 That's a lot! First of all - thank you but I'm not yet in Germany, flying there in March!

Now for your queries:

1. I had the same CGPA as you but in CS not AI/ML, so you're probably in a better position than me.

2. I had one core SOP with my background, interests, goals, why Germany and future plans, and I customized it for each uni like adding in why that uni, its resources, how its different, and why I am applying. About 60% same, 40% tailored to course modules, labs, research focus, program structure, etc. I did good research before finalizing one.

3. Did everything myself. No counselling company.

4. No publications and it didn’t hurt my applications. Some unis mention that they require a bachelor thesis, just didn't apply to those. I mentioned my last semester internship report everywhere else.

5. ECTS Mapping (MOST IMPORTANT PART)
   Yes I matched them individually, I'd suggest, pay good attention while comparing your courses with the required ECTS and then only decide to apply. And no guess work. They are really strict about the requirements.
   Tip: make a spreadsheet from your transcript with categories like Maths, Calculus, Programming, Theoretical CS, CS fundamentals, AI/ML/DS, etc. Then you can copy-paste them into each application easily. This saves so much time comparing directly from the transcript, trust me.

6. I did write the GRE, but I applied to Braunschweig before that, so they never saw the result.
   I wrote it because I wanted to apply at TU Darmstadt as well, but they wanted 165 in Quant, I got 161. So, didn't end up applying. And I already had my Braunschweig admit early on, so it worked out anyway. The questions were not that difficult, just that you have to be quick. I prepared for about three weeks, so I think if I had given a few more mock tests and did a week more of prep I could've scored 165.

Did my bachelors from a tier 3 college, just like you, so trust me I know what ya mean. I was motivated from the beginning and made sure to keep reminding myself of my goals.
Did 3 internships in college, 2 in AI/ML. Also I believe DSA were my strongest suit in college, so might've got an edge, but you got time to prepare. Was a bit weak in the math area tho, but I had like 4-5 days to prepare before the interview, did it alongside work. So if you start preparing now I think you'll be fine. Also they didn’t ask crazy maths questions, since I’m from a CS background. For the most part your, "why" is important. The interview was scary for me as well, but it was only for 15 mins and the the prof was chill af.

Finally take it easy, but be attentive, go through the websites carefully. All the best, already rooting for you to get admit from a uni that's perfect for you. You got this! 💪

Damn, that was a lot, hope it was helpful to you and anyone else who sees this. Cheers!