With practice you can get a riffle under 2-3 seconds without weaving. But if 7 still seems too much, do less but do a running cut or overhand shuffle between two of the riffles, like riffle -> riffle -> running cut -> riffle -> offer to cut -> deal. I heard this is what casinos did in older times, and they do have a direct interest in not making the shuffling too long (less hands played) or too weak (can be abused).