I don't have a favorite shot. I don't even remember 1/2 of my shots. Today I have 200GB of unedited images on my drive. Tomorrow I shoot a video. Sunday I shoot a spec-editorial. I look at thousands of pictures everyday of my life and I retouch so many that none of them really make much of an impact.
So to answer your question, I don't have a favorite shot.
But I do remember the photography I did earlier much more than the photography I do now. Like how you remember your childhood more vividly, it simply makes more of an impact when it's fresh. When I was young and impressionable.
If I had to pick one, I'd pick this one:
Why? It reminds me of a simpler time. A time when there were no expectations of me to do great things. A time when I could learn and not be expected to produce. A time when monetary gain had no place in my career. A time when I knew nothing and had everything to learn. A time when I couldn't get a model to save my life.
So it's my favorite for sentimental reasons but nothing photography-related or photography-specific.
But there's plenty to be said about how the journey unfolds and life changes along this path. Perhaps that's the purpose of this exercise. It's got nothing to do with the photographic elements. But that was certainly a "snapshot" of my life when I was simply a budding strobist and the name "LUCIMA" hadn't even been invented.
I suppose if there's anything to be learned from this answer it's "remember where you came from". Because when things get crazy, you're going to miss this point of your life. You're going to miss the innocence and simplicity of being a student. Hopefully you never lose the curiosity and thirst for knowledge.