Latitude-sorry to hear of the sit bone issues. All I can offer is there a solution. 30 miles should just be a start and not the end. Heck-there are a number of us that ride a lot of miles and even on back to back days and saddles are not an issue.
My experience has been too much padding in the shorts is not helpful-sounds like you might be getting there as well. I've had good luck with Selle Italia saddles so you might check some of those out as well. I've been using the SI Prolight gel for several years as it's a little wider than the Flite and others-plus it has a cutout. The type of rail on a saddle can make a difference on how much road vibration you pick up, too. Good luck-there should not be a issue with doing rides 60-100 mile due to the saddle.
Just a thought, but is the saddle height okay for you? Too high can cause issues as well.
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