Glass fibre (AKA Garolite) and other composites will not stand up against impacts or crushing - I have tried it several times with poor results. Composites are great for internal parts, but not armour. Titanium will work well but for full combat you will need at least 3mm; 1mm sheet is surprisingly bendy and will not provide much protection. Even 3mm Ti will fare badly against spinners if they catch an edge so recess the top and bottom behind your side armour.