The top audio challenge is to balance the music and the voice of our anonymous host to help the listener immerse in the story. I address it with a selection of iZotope tools. RX 6 is my go-to solution, and I also use Neutron, Alloy 2, and Ozone 7 to create the best sounding experience I can. The podcast is still being recorded in a spare bedroom somewhere in Australia, and there are a lot of challenges that come with that such as background noise, barking dogs, and neighbors. It's safe to say that without iZotope I would be lost!
Having invested in some of the Waves and Native Instruments audio plugins, I have never invested in iZotope. I only hear good things though.