RE: Third Plane
My turn, blast me if you will but it is my opinion and personal experience.
4*, Tiger 2 ect.. are not, by far, the only choices.
Look for anything that has no more than 25oz wing loading, less is better. Avoid tapered wings (they are more likely to tip stall)
Planes I have flown that I think someone with skill can move into as a second plane (with skill means you can do any of the basic aerobatics with ease on your trainer and land comfortably every time)
Piper J3 Cub
Cesna 182
SpaceWalker 2
RV-4
Hanger 9 P-51 PTS
There are many others that should fit the bill, read reviews of specific airplanes and ask here.
Everyone is different and only you and the people you fly with can judge your ability and recommend a plane.