On the shins, you should have made the middle section at least 20mm wide and have the top and bottom wider to glue the strips on. The best thing to do is offer your joining strip onto the armour before you trim it and mark out where it will go. You will find the cut is not the same width on the joining edges of the armour because of the wonky nature of the original armour. It's okay to leave the flat edge underneath showing.
Try and keep your corner cuts of the joining strips to a minimum or even leave them squared. They look a bot too big.
Also, your belt. You should really line it up on your abdomen, not your groin. The belt should look off-centre when positioned correctly.