Well, it looks like we were both typing for quite a while.

Some of your choices for "third plane" are advanced sport planes, a little quicker and/or more capable than the Rapture .40 - these would include the Super Sportster and the Hog Bipe. These are excellent airframes, but not wildly different in overall performance from other sport planes. These are good, "safe" choices for third planes. Other sport planes like the Lanier Shrike and the Great Planes Patriot XL are higher performance versions of advanced sport planes, as well.

Other choices like the U-Can-Do, the Tango, the Twist, and the Funtana are 3D/Fun Fly planes. They're quite aerobatic and more capable than typical sport planes, but don't fall into formal pattern or IMAC aerobatic categories like the airframes I mentioned in my previous posts. This is a very broad category that includes a lot of airframes you haven't mentioned - Great Planes Dazzler, Tower Hobbies Uproar, H9 Showtime 50/90, Model Tech Magic 3D, Model Tech Magic Forumula 3D, Model Tech Twister, and most every profile glow ARF or Kit on the market like the H9 Tribute 36, Sig Ultimate Fun Fly, Sig Fazer, Tower Hobbies Fun 51, etc.

All of the 3D/Fun Fly planes mentioned above (and many, many more) will make good "third" airplanes if 3D acrobatics are of interest to you. These planes will generally have thick airfoils and can be slowed down and landed gently enough. It's when you have them whipping through the air and rolling so fast you can't count the number of rotations that they differ from sport planes. By most accounts, the Funtana and Showtime airplanes aren't reported to be particularly difficult to fly, you'll simply want to work your way up to high rates while you get used to the large 3D style control surfaces.

Your 3rd category of interest seems to be scale civilian aircraft - such as the Piper J3 Cub and the Cessna 182 on your list. This would actually be similar to the IMAC scale aerobatic category that I mentioned previously, but the J3 Cub probably wouldn't be very competitive at an aerobatics competition. Other airframes you haven't mentioned that fall in this category would be the Citabria, Decathlon, Super Decathlon, and Clipped Wing Cub ARFs available from a number of manufacturers in various sizes. Technically the Ultimate Biplane is civilian scale and quite IMAC capable. Many pilots report that they've successfully flown the Ultimate as a third airplane, but I would suspect they spent a good deal of time gaining a lot of experience with their second plane before moving up.

How a plane is categorized really isn't the most important thing. This thread has mentioned dozens of great airframes for "third plane" choices that cover a wide variety of options. There are many dozens more that haven't been mentioned that would be great choices as well.

Generally speaking, the only flying characteristics that you need to avoid if possible in a "third plane" are airframes that easily "tip stall" and dip a wing if slowed too much while landing or if taken off too quickly. If you can take off and land the airframe, you can adjust the engine power and control throws as you see fit while graduating from a "second plane" to whatever else you decide to fly. General categories of troublesome planes can include scale warbirds that tend to tip-stall and/or nose over when taxiing, scale aerobats like the Cap 232 that can tip stall or snap unexpectedly if over-controlled (low rates will prevent this while learning).