I've tried a lot of pillows over time. I had insomnia for like 20 years. When I was having bad acid reflux, I ended up investing in a MedCline pillow:
Discover MedCline's therapeutic medical pillows for effective nighttime relief from acid reflux & shoulder pain. Shop now for a peaceful night's sleep!
medcline.com
It has 3 main features:
1. You sleep at an angle (upper torso lies on the pillow)
2. There are arm-holes on each side to stick your arm through. GENIUS.
3. It has a maternity-style pillow to put under your neck & wrap your legs around
My reflux was solved later with medicine for my stomach condition, but I liked the pillow so much I still use it to this day. I have a cheap memory-foam mattress from Amazon, plus a "heavy" blanket (weighted blanket). I sleep like a baby now. I'm usually out in less than 5 minutes. The pillow is super expensive, but it's just a fantastic design if you have trouble getting comfortable at night.