I agree- if all we needed was someone with an advance degree to review the literature for 100 hours and all of us would have successful treatments- we wouldn't be here.
This is why Dr Pimmentel and Seibecker have such a following- they have tons of experience- and even they think this is tough to treat and different cases require different strategies- sometimes herbals, sometimes antibiotics, sometimes ED and sometimes all three.
I think you should try to avoid doing restrictive diets long term- but sometimes this is hard- if you truly dont feel good on a variety of foods.
I think the goal would be to try to be on something like the Cedars Sinai Diet- which pimentel says is varied enough to encourage microbiome diversity while reducing fermentation potential.
However it is nice that OP tried to review the literature and come up with some ideas about an approach that is different than a lot mentioned here. OP- if you are more interested in a herbal/naturopathic approach I know that Dr Seibecker recommends this book- has information about recommendation on herbs and other stuff as well. https://www.amazon.com/Functional-Gastroenterology-Assessing-Addressing-Gastrointestinal/dp/0692864660
Dr Ruscio's book also covers some of the herbal approachers as well.