I can still see it; I can still see his face: a face which days prior, was warm and full of joy; a face that could make anyone smile.
You did a great job with this.. I sense that you are the kind of talented writer that tends to write too much because you are good at it. So it is important to edit out the 'extra' content. For example:
I can still see it; I can still see his face... ---- Even though it all has that feeling of inspiration, I notice with my own inspired pieces of writing that I can always improve it by editing out some of it after it has been written.
I can still see his face -- a face which, days prior,
was had been warm and full of joy; it was a face that could make anyone smile. --- I edited this for semi-colon and comma use.
Use the rule called 'number agreement' here:
people strive to achieve their own unique version
s of ...
No need to capitalize the word when it is used as a common noun:
so few
u niversities...
Well, I don't know what to say about the loss of your brother. There is no consolation for something like that. Be strong for your family, and stay focused on this 'good life' idea. You did a great thing by showing the reader that your plan for a good life is connected to the decision to enter this program for microbiology; the reader will feel compelled to open doors of opportunity to you because you have a clear vision of what you intend to do.
I still think you could add a sentence that succinctly expresses why microbiology can lead to the good life and what is a good definition for 'the good life'.