I also have a Venus with OS 46 FX. It is a very good plane but it needs more than the 46. WIth it, the plane needs speed to complete vertical maneuvers. For example, it struggles through the top of a vertical climb with 1/2 roll and and pulling one the elevator to complete the 1/2 loop. Outside loops are really small. I tried everything between a 10x6 and an 11x7 (settled on this last one). I've heard the OS 70 FS turning a 12x9 prop will make the trick.

Also, being a small plane, you would need to fly it closer but it looks like it is rushing through the pattern.