A few years ago an olympic athlete was being interviews on TV about her training regimen. After describing it, she said, "keep it fun". How true. I cannot overemphaize the importance of keeping your training fun. Whether you use workout snadbags or any other piece of exercise equipment, you gotta keep it fun.
Functional fitness is not just a crash course to get ready for the next game. It is a lifelong quest to stay fit but more importantly, healthy.
So, whatever you do, keep it fun! Use variety, novelty, and sport to keep in shape and health for life. Take vacations where you can do your sport. Consider stopping your training on vacation to give your body a recovery period. Swimming, hiking, and maybe some stair climbing can substitute for the formal workouts you do at home. Keep it fun! Here is more sandbag training advice.