1. Will any of these keep me awake?
2. Are all of these effective on an empty stomach?
3. Does anyone have any other suggestions to help sleep and remember dreams?
3.
For sleep, I strongly recommend 5-HTP, a serotonin precursor, over any other supplement, including GABA.
For remembering dreams, I recommend Bacopa over Ashwagandha. Ash has some great physical/anti-stress properties, but Bacopa is better for memory.
Finally, Niacinamide is a vitamin B analogue that's really helpful for sleep. Niacinamide doesn't have "flush" effect that plain Niacin has (though I kind of like the flush).
2.
empty stomach is usually better.
1.
Piracetam is a neurostimulant, I'd drop it.
Also, L-theanine while it does promote relaxation, doesn't cause drowsiness. In fact it actually lowers serotonin levels. Personally, I don't take theanine before bed, but it could work for someone who is too tense to get to sleep.