What printer are you using? Your pieces are coming out so dang good!!!
Staple welding for joining parts! I use staple welds with adhesives as well, or epoxy backing the seams with the welds.
LadyRedCos's Artaius helmet was staple welded with epoxy backed seams and I took a dive in that helmet with no irripairable damage or seam splits. Can't recommend it enough but there's many choices, that's just what I prefer.