Do not worry too much about the weight; make sure to reinforce the frame, especially in the most delicate area that is subject to stress, which is the steering zone. Check all the bearings thoroughly; there should be no play. When you sit down, the seat should not lower by more than 2-3 mm at most. Also, do some stationary tests by braking with the front brake; the fork should move as little as possible, and there too, the wheel should get no closer to the frame than 2-3 mm at most.
@marcoruga your advice is very much appreciated Marco! Will add some more carbon layer for reinforcement. As for the headtube bottom bearing losseness I'm still figuring out on the solution. Noted on the front wheel breaking test. Will do as you advice.
