The Messenger series is pretty good too. Space dilivery guy finds a big ancient super powerful mech/AI and his rag tag team has to fly around the galaxy fighting alien bad guys, restore the mech/AI to full power and save all sentient life from the big bads. There are 15 books in the series. Most of the books are also available on audible too.
https://www.amazon.com/Messenger-Military-Scifi-Epic-ebook/dp/B07W6G5T5C