Why are you forcing extra carbs from grains?
The only way to add weight from diet is to add body fat. At the moment it sounds like you are aiming for skinny fat and that is not healthy (or a good look).
The healthy way to up your weight is by adding muscle. Do some strength training.
Up your fat for fuel, eat plenty of protein for muscle building and drop the grains.
The "Seven Deadly Sins"
• Grains (wheat/rice/oats etc) . . . . . • Dairy (milk/yogurt/butter/cheese etc) . . . . .• Nightshades (peppers/tomato/eggplant etc)
• Tubers (potato/arrowroot etc) . . . • Modernly palatable (cashews/olives etc) . . . • Refined foods (salt/sugars etc )
• Legumes (soy/beans/peas etc)