I don't think I was very clear with my original post.

I was definitely going to use some weight of batt insulation. What ever I can fit in the joists, I haven't opened them yet.
My intended question was what if anything I should put at the ends of the batting to block wind from coming through the bricks.
also I have an outside spotlight, which needs sealed off, how should I do that?

To be honest I am more concerned about the livability of the bedrooms above the garage than I am in the garage itself. The temp last night in Pittsburgh was danged near zero, that was cold.

Plus I realized that I made a typo, the garage is 25 foot long, not 35. With that length,and the idea of using it or general tinkering would you use two or three light fixtures, and would you put them on a separate circiut? What about a dedicated power outlet for tools? I don't have anything that big yet, but it is probably only a matter of time.

Or should I just put in a small secondary breaker box in the garage and be done with it?

Any suggestions with he further details would be appreciated.