She's been on Planet Money and discussed her ideas, where they come from, etc before. I don't think I'd quite do them justice explaining them myself. Apparently she's now a chair of the FTC as well (which I was unaware of).
If you want a raw view of her views on anti-trust: https://www.yalelawjournal.org/pdf/e.710.Khan.805_zuvfyyeh.p...
In one of the podcasts she dives into the history of anti-trust. She talks about how after Standard Oil we convinced ourselves everything was a monopoly and stifled a lot of innovation, which led to some reforms later and the anti-trust we have today which are demonstrably too permissive. She has picked on Amazon (as a wider corporation) quite a bit, but a lot of it has to do with the practices of their ecommerce division and the extent to which Amazon can compete with it's vendors. Basically, she believes there's a middleground to be found between the two anti-trust time periods and that it's important to be concise in how we do that. You can see some of her specific criticisms in the article above.
A more full bibliography can be found here: https://en.wikipedia.org/wiki/Lina_Khan
I highly suggest "The Separation of Platforms and Commerce" as that's the one that resonated with me, having worked in the startup world.