Don't confuse the strainer with a trim device. It is only there to try to even up the elevator control forces. The reason you are experiencing a balancing act to get the plane trimmed up in cruise is because the main wing has largely been unloaded with your configuration, so the pitch is primarily controlled by the canard. This makes it a bit touchy. Try introducing a little up reflexor in cruise, then trim the elevator above neutral and I think you will find the pitch more stable because you will be "cradled" between two lifting surfaces instead of balancing on just one.
As a side note, if you send me a photo of your plane taken from the side standing about 20 feet from off the wingtips and looking perpendicular to the fuselage (stand midway between the projected/extended canard and main wings), then I can tell you what your decalage is. This is useful to know, when comparing your plane's behavior to other flying Q's.