Well as Jay said, that all looks pretty sane, a clear sign that you're under pressure from the house move I suppose? Something like that would have good market potential I think but keeping the weight within limits will be your big challenge. A couple of points - you need to get familiar with Pt103 - you can't have a 75kt cruise so there's no point in designing for it, it will only be a weight hindrance. Your max S&L speed is 63mph/55kt/100kmhr, power-off stall speed must be less than 24kt/28mph/45kmhr (no mention that it has to be clean but I'm sure you're going to need about 20% more wing area unless you have an airfoil with exceptionally high CL), max empty weight of 254lb/115kg, max fuel 5gals/19lt - the fuel restriction benefits a series hybrid to get more endurance/range provided you can get down to the max empty weight which, with a 26.5hp MZ175 at 15kg, is possible but not easy. I'd stick with a 10hp electric motor, don't forget they have far more torque than an ICE and you can overload them for short bursts provided the cooling is effective. I would raise the electric motor to get the prop higher so as to avoid FOD from stones thrown up by the nosewheel - they do get thrown up even with the best wheelpants, mud flap or whatever device unless it's a flat plate under the prop, because the stones might get deflected down initially but they bounce back up again - guaranteed - and it doesn't take many prop strikes on full take-off power to wreck the prop. I would get rid of the cranks in the mainspar for structural and ease-of-fabrication reasons, particularly since you need the wings to be removable so they would presumably have plug-in stubs extending from the spars of the wing panels, those stubs would be most easily resolved into the wingbox if they slide in parallel to the wingbox spar.