If you wish to improve range of motion one might think to start doing yoga. If your goal is to increase core strength you might think Pilates, and if you want to improve your strength you might wanna do CrossFit 7 days/week. If your goal is to improve your overall fitness you are doing yourself a disservice by doing the same workouts day in and day out.
The truth is most people should be diversifying their training disciplines on a weekly and/or daily basis. Finding time to squeeze in classes or workouts of multiple training styles will increase your overall fitness while also helping avoid over-usage injuries. Diversification will also help you stay stimulated and goal oriented. You can more easily see where adjustments need to be made to improve muscular balance, both antero-posterior and bilaterally.
Changing out your normal routine is as simple as signing up for a multi-discipline training facility, joining ClassPass, or making it a point to try a new workout style every month.