If you make sure the spell list doesn't have any encounter-ending spells at 1st level (Sleep, Color Spray, maybe a few others), you can seriously frontload them with 1st level spells per day. That alone will alleviate a lot of issues, as they'll have enough spell slots for the day + a bit at level 1, and when they get higher levels spells they fall into the usual paradigm of having more than enough spell slots spread across the levels.
You forgot to mention in the Crystal Warrior that they don't get Grow Crystal at 1st level (that or it's just not on the table).