Feedback on dryland regimen

Hey folks, I just started up a dryland program for my team last night (I'm participating in it, too, not just overseeing it), and wanted to get y'all's feedback on aspects of it. We're offering the dryland workout three times a week after practice, after two of the evening weekday practices and after our Saturday morning practice. It's designed to last about 30-35 minutes and be achievable for folks of all ability/fitness levels. Here's about 90% of the workout we did last night. There are a few exercises that aren't on the list, mainly because I've forgotten what they're called. All told, we did 10 or 11 exercises for each section. As it stands now, the format for each workout will be 3 stations set up, one for ab/core, one for legs, and one for upper body exercises. Folks will spend approximately 10 minutes at each station and then rotate to the next. Up till now, my dryland experience has either been participating in dryland as a USAS athlete or writing dryland workouts for teenagers. Since we've got a wide variety of ability/fitness levels participating in these dryland workouts, I decided that, instead of a specific number of reps (ie, 50 crunches, 30 squats, etc), we'd do each exercise for a specific time. Last night we did 45 seconds of each exercise, then rested for 15 seconds before moving on to the next one. That way I figured that everyone would be able to get as much as they wanted out of each exercise without forcing them to possibly overexert themselves. Abs/core Crunches with feet on the ground Crunches with feet in the air Right obliques Left obliques Flutter kicks Donkey kicks Bridge Plank Legs Squats Calf raises Lunges Stair steps Streamline squat jumps Broad jumps Side lunges Wall sits Upper body Regular pushups Wide grip pushups Diamond pushups Dive bombers Arm circles with arms held out to the side Facedown tricep raises Rows Dips This was all bodyweight stuff, with no weights, stretch cords, medicine balls, or anything of the sort. I've got stretch cords and medicine balls on the way, just didn't have them in time for last night. They will become a regular part of the workout when they arrive. With all this said, here's what I'm requesting feedback on: Is 45 seconds on, 15 seconds off a suitable time interval? I was whipped by the end of the workout and, as the coach, I didn't even swim practice beforehand! Should I drop it down to 30 on, 15 off? Should I stick with 10-11 exercises per station and have folks only do each exercise once, or drop it down to 5 or 6 per station and have folks repeat them for the 10 minutes they're at that station? Are the exercises too rigorous? Like I said, I was whipped by the end of the workout, and I'm in better shape than most of the other people who will be participating. Any other bodyweight exercises y'all can think of? I've got almost all of my cord/medicine ball exercises lined up, but would love to hear of more bodyweight exercises. What do y'all think? Thanks!