I would have gone at least 1 stop brighter on the first one and 2 or 3 brighter on the second one. The trick is kind of "fooling" the auto exposure into doing what you want. For example in the first shot, the camera naturally meters for the center of the frame which is the lit up garage in the distance. You want the car to be a bit more prominent, so you should use the AE lock to get a meter reading for the car instead of the lights themselves. You do this by aiming at the car then pushing the shutter halfway down, let the camera do its focusing and metering, then hold it while you reframe the picture. As long as you don't let up your finger it will retain the settings.

This works better if you have a spot meter setting. Also if you have an exposure compensation setting or manual controls it's a good idea to bracket your exposures, i.e. take the pic at a few different EV levels.