Replacing exterior door jamb

Greetings! I want to replace the door frame with a new door frame on my exterior door leading inside my garage.

I know there is door frame kits that one can buy at the local home improvement stores but I want to look at making my own.. my questions are

1. Do I just copy what the current build is??

2. Any opportunities for improvement on the current frame that I could incorporate in the new one??

3. What type of wood would work best??

I've attached a picture collage of my door for everyone to see.

I also want to renovate the current door... sand it, stain, seal and paint. Put up a sheet of polycarbonate where the glass once was. I replaced the hinges already as one old ones were rusted and bent due them being detached from the existing floor frame.

I think I have the necessary tools to do the project.

1. Router (door mortise)
2. 10 inch miter saw (door frame)
3. 6.5 circular saw (door frame)
4. Saw guide for my 6.5 inch circular saw
5. Hammer (nail the frame) ..

Please provide feedback..

Thank you !