Staining over previous tinted stain on pine playset

We're in Georgia and have an expensive, year-old pine playset in a shady spot of the yard, stained in a redwood tint (from the manufacturer). I'd like to start refreshing the stain every year or so to keep it in great condition, especially with another kid on the way. It's been gently power washed in anticipation of restaining. Based on my limited experience in Georgia thus far, the incredible amount of pollen we get on surfaces in the Spring means mold on wood surfaces. Is this a job for Defy Extreme? And just as important, when staining over the previous stain, do I continue to use a tint, or should I be using clear?