If it climbs when inverted then its TAIL heavy. Generally, when it tuck towards the CANOPY in a KE then its NOSE heavy like you said. I would normally set my CG by flying inverted and any KE issues be tweaked by moving the CG a bit and eventually mix it out. Looks like you have to mix out the coupling in KE. Being a profile might your wing incidence be out? Just a suspicion. You will hardly find 'perfect' KE planes. I found the best so far to have been the EF Extra 300 EP and my Fliton Extra 330. Both will give you an amazing KE once you set the CG right in the sweet spot. I do not need any mixing.