I was on all the PPIs 6 months ago (when docs thought my peri nausea was ulcers) and they made me very unwell. Stopping stomach acid made me unable to digest food properly and I had very bad reflux (which had never had before I started the meds!) when I tried to withdraw. They keep the gastrin hormone elevated which can interfere with other hormones, however, they're probably a key med if you have a hiatus hernia.
Ranitidine made me feel very anxious too so although these are milder than the PPIs, they seem to have a bigger effect in the CNS.
A lot of reflux, particularly if over 40, is due to low stomach acid, where the food can't digest properly and gets regurgitated. Digestive enzymes are good for this and will show you if it's too high or low. Slow transit from peri is possibly the main cause though.