You can reduce the time there by making the water colder. You can also approach the experience as a sequence of steps and work out how you can wash every single part of your body in the least amount of steps.
For example, is it quicker to get all wet, turn off the shower, lather up your body, then rinse it all off in one go, or is it more efficient to do it from top to bottom, one body part at a time?
What's the fastest you've been able to go from sleeping to walking out the door having had a full shower?
Finally, you should probably have a shower once a day if you're around other people or if you get visitors. You might not smell anything, but they definitely will.
Finally, there's absolutely nothing wrong with zoning out in the shower. Some days you luxuriate in the experience, some days you don't.
Good luck!