It may not exactly qualify as an attraction, but we enjoy walking around Pointe Orlando. That is an outdoor shopping center near the convention center. It has some nice shops, restaurants and a movie theater. It is also adjacent to Wonderworks science center and not far from Ripley's museum.
At the other end of I-drive, we go to Belz factory outlet to visit the 2 Disney outlet stores.
Also, we haven't tried this yet but drove past it last trip. There is a huge go-kart track, multi-level, on the main section of I-drive. We're planning on checking it out next time.
Steve