My ds, 11 months, has been quite bad with reflux too. He was on gaviscon and whilst it did help it also made him so constipated that he was sick anyway straining!
He has gained 1oz over the past 2 months because he has been so sick after most meals approx. 5 out of 7 days. He is a great eater and not fussy, the problem is keeping the food down. We are now trying a little and often approach to feeding now and for the past week he has eaten really well. I had previously given him whatever quantity he will take but it seems that his stomach just can't cope with volume.
I've taken out eggs and yoghurt as these also make him sick despite liking them. I have been giving him alpro soya yoghurts, the plain one mixed with mashed fruit. He doesn't show any other signs of a dairy intolerance so I think maybe he just isn't ready for some foods.
I haven't had much advice or guidance from health professionals and I have never heard of orange food being worse, although I did read about tomatoes being a culprit so I have also cut that out for the time being.
If I give him mashed potato I do need to put lots of butter in it as he also gags, it seems to be too dry for him, often I will give him it with something with a little gravy/sauce to help. Other mashes seem to be fine for him.
Is it a textural thing for him that he doesn't like? My ds will eat bananas as long as they are whole and he can bite but he will refuse them mashed. He also prefers buttery mashed potatos to non mash.
It is all trial and error but I do understand your frustration. My ds is a poor sleeper too and I understand the lack of sleep too, he used to sleep max 5-6 hours solid prior to weaning but after weaning he hasn't slept any great length at a time and it is heard going when you're working too.
Has your hv or doctor been any help? I was referred to a paedtrician but I just got the blank look or eye rolls whenever I stressed how sick he was as until now he looked not too bad on paper! Although he did go from between 50-75th centile down to 0.4 and is now following the 2nd line. Following a line in my opinion is not enough, nor how good he may look on their charts, it's what happens from day to day that matters too. My worry was that ds wasn't getting enough nutrition.
Sorry I've not been much help, and for the essay!!