I dont know much about it
but I did find this.
So basically you are extending your 'doing things' days by using the "plus" experiences vs getting another park ticket for those 2 days.....so 4-day ticket, + 4 experience credits on the off days. I don't know how much extra the "plus" costs (we have an annual passes with the plus option), so I guess you would need to figure out the value of those plus experiences you are going to use vs just getting a park hopper ticket and paying for those experiences out of pocket.
Admission to the water parks is $140 ($70 x 2 days) and $30 for the mini golf ( $15 x 2 rounds). So if the hooper plus is less then $170 per person then its worth it.
as always, I would call and make sure there are no hidden issues or regulations that would not let you use the 'plus' perks on non-park days, but on the surface it looks like a good plan.