They show your play style in the game throughout the entirety of Wangan Maxi 5.
It's "Wangan Rookie."
Titles don't increase. You can choose whether to use a title or not when you earn it. You can keep changing to your new title, or you can keep a title that you like forever.
Please see the "Titles" item in the "Game Description." Some of the earning conditions for titles are published there.
There is no strength or weakness in titles. The strongest title is the one that you like.
You can check it on the Car Data Confirmation Screen (1/8) on the drive cabinet and the Wangan Terminal.