The heady/mental high followed by a crash is most likely because you took them at still a high % clear. Try letting them go all cloudy- that crash might remind you of the Beasters crash, whcih is EXACTLY that.
For purple colors in purple strains, check out SnowStorm aka PurpleMaxx. If a plant CAN turn purple, the hormone (kelp-derived) will maximize the purple coloration.
Your plants look very very healthy and to be yielding really well. I've always thought the Soma Lavender was beautiful, and your cross looks great.