Pusher configuration is good for simple electric propulsion installation.
20kW electric motor + folding prop (like from Helix) would be nice.
Small problem is with designed MTOM - only 185 kg.
If EW is 110 kg and you remove 30 kg for engine....
en.wikipedia.org
.... than airframe weight is arround 80 kg.
Typically you need to have reserve for pilot at least 100 kg (I suggest 110 kg - lets be realistic)
So 75-80 kg for airframe + 100-110 kg for pilot.
You need also 20 kW electric motor (10-12 kg) + controller (2-3 kg) some wiring and... battery.
Min. battery size would be 5-6 kWh = arround 30 kg weight.
"Optimistic" summary...
75 kg airframe
100 kg pilot
10 kg motor
2 kg controller
30 kg battery
==========
Airframe should be designed and tested for at least 220 kg.
However for "real life use" and flying also in harder conditions I would recommend to design airframe for MTOM above 250 kg.
For comparizon - technical parameters of EXEL from Alp-Aero:
View attachment 116556
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all-aero.com
Wing span: 13.74 m (45.1 ft)
Length overall: 5.90 m (19.3 ft)
Propeller diameter: 1.28 m (4.2 ft)
Wing area: 11.62 sq.m (125.1 sq ft)
Aspect ratio: 16.2:1
Weight empty*: 190 kg (432 lb) - *incl. ICE engine with approx. 20 kg installation weight
Max T-O weight: 310 kg (683 lb)
Max wing loading: 26.67 kg/m2 (5.46 lb/sq ft)
Cruising speed at 75% power: 120 km/h ( 65 kt, 75 mph)
Max speed: 180 km/h ( 97 kt, 112 mph)
Stalling speed: 64 km/h ( 34 kt, 39 mph)
Max rate of climb: 2.2 m/s (434 ft/mn)
Endurance: 3 hours
T-O run: 150 m (492 ft)
Landing run: 140 m (459 ft)
Best glide ratio: 30:1
Min rate of sink: 0.75 m/s (148 ft/mn)
G limits (operational): + 4.4 / -2.2 G
Seats: one pilot