That downthrust looks excessive. I would half it and if possible mount the engine inverted. You can actually compensate for less downthrust by making your plane slightly nose heavy.The Senior Cadet is just about the worlds easiest trainer. Very very forgiving.
It also flies much better (tho less stable) with only half the dihedral. You might want to buy a wing kit (from the regular kit) and build it with less dihedral