If there isn't wind or waves then your fastest, easiest, best SUP option is to use a canoe. They're already optimized for glide. And cargo. And passengers. Or go C1. Whatever your druthers. The only benefit of a SUP *board* is for surfing and its low windage. Otherwise all benefits -- and they are major -- go to the canoe.
And if you ever encounter shallow water, use a pole. 12' x 1" tempered aluminum. (I'm the only widely available producer, $50, see my site http://outyourbackdoor.com.)
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