I see that you put your location in. Thank you. It really helps with answering questions.
Don't insulate until you make sure you have those leaks fixed. And when you run your wire for outlets, make sure you put quite a few in so you don't have to drag out extension cords. Also when you are running your electric, add an outlet or two on the outside of the garage. They come in very handy.
If you or your wife, or both, like to decorate for Christmas using Christmas lights, add an outlet or two up at the top right underneath the soffit.
Add a couple of 500w Halogen Floodlights also. There will be quite a few times that you may have something going on in the driveway at night and need to light it up. When you run your electric from the house, try to plan on adding a switch (a 3 way switch) to where you can switch one of the floodlights, or a couple inside lights on or off from inside your house. And when you run your electric, also plan on running Cable, telephone, and maybe Cat 5 wire. Depending on the distance the garage is from the house, you may want to think about adding an intercom in. I know I wish I had done it. As it stands now, my wife calls me on my cell or I call her if one needs something. For instance if I have to make a parts store run, I'll call her to let her know instead of walking up to the house or out to the other end of the property. An intercom would be really handy.
I think there is a thread or two on here about pre-planning for the electrical needs, computer needs, phone, etc for in the garage. If I run across the threads, I'll post them for you. There is some really good ideas in them.
And WELCOME TO GARAGE JOURNAL