By Richard Horgan Los Angeles (Knewz) — Lee Thompson spotted an opportunity some years back. So he co-founded Flash Pack, a group tour company aimed at solo travelers in their 30s and 40s. “Our maximum group size is 14 and 90 percent of our groups are sold out,” he tells Knewz.com from his U.K. headquarters. “Before Flash Pack came along, the only options for group tours was with 18 to 30 companies for over 50s, so we spotted a gap in the market for 30 to 50 year olds by creating an aspirational brand and making group tours appealing.” “We do everything we can to protect the group dynamic so w…