I'm an engineer and non gardener, so please excuse any lack of knowledge when it comes to herbs.
I have recently become a distributor of Aloe Vera products, and now have started a program of educating my self of the use and benefits of this plant. I came across this web site in the links section of a rivals web site.
I notice some of the entries in the forum advocate the ownership of a plant or more, to mix with other herbs. I am told that the aloe vera is related to lilies and garlic families of plants, do this mean it's a herb?
My view, in answer to your question, is that any edible plant which has medicinal properties can be considered a herb - this includes trees and some fungi.
The difficulty with using products which have been produced by synthesizing various parts of a plant is that the products may differ widely from the original plant material and their value may be diluted depending on the percentage of original plant the product contains. There also may be problems with manufacturers trying to "standardise" a particular ingredient and thereby concentrating it or using a part of the plant which is not normally used. The examples which come to mind are standardised St Johns Wort tablets and kava kava preparations which are made from the leaves which can be hepatoxic (damage the liver) rather than the root, which is the traditional usage.
I have been growing and using aloe vera for the past ten years or so. Obviously it not a native of this country and its usages have been gleaned from people in the south west of the US where the plant is a native. (It's worth visiting the Eden Project to see it growing in its natural habitat.) I use the gel on the inside of the leaves for instant burn relief after initially cooling the part down with cold water for ten minutes. I know it's really helpful for people of all ages for this problem.
I've also made a sunburn lotion with aloe vera gel and SJW oil which was very successful.
I understand it is useful for dietary difficulties when you can ingest the gel. I've been told you have to be careful not to scrape off any of the yellow inside skin or it makes the gel bitter. I've not used it this way because I have loads of other herbs I would turn to first.
I really like aloe vera plants because of their sociable nature. You might find that a strange description, but over the years, my plants have produced hundreds of babies. I have given those babies away to other people and I know that they have been similarly generous to their friends and family. Energetically, aloe vera is supposed to help ward off accidents, so even if a person doesn't want to use it medicinally, it can be a helpful ally in the kitchen!
The plant is also very difficult to kill, unless you leave it without water in a draughty situation. (It doesn't like being behind a curtain on a windowledge in winter! This means it's a really good plant for giving to people who think they can't grow anything.
I don't know if I've answered your question in the way in which you wished, but my final suggestion is grow your own plants, get to know them, use them and see how it helps you.