Here is a quick review of one of the new GURPS PDFs from the 2020 PDF Challenge. I chose this one to read first because I like mercenaries and the Action series always delivers.
GURPS Action 7: Mercenaries
by Shawn A. Fisher
This book is focused on providing the tools to run heroic mercenaries using the GURPS Action line. It can be played realistically, of course, but it contains rules and guidance aimed at action movie heroism. You're the Good Guys, and you fight the Bad Guys, and you get paid to do it.
The book contains a 20-point lens suitable for making a mercenary out of another Action template. It provides guidance for using the templates from GURPS Action 4: Specialists, guidelines and pay (and how to handle it with Wealth levels, instead), Patron costs for units, and what to roll to establish a contract.
There is section for the BATTLE system which quickly resolves larger conflicts, while providing casualty figures for both sides and chances for PCs to get some individual ass-kicking action. Random "Challenges" and set-pieces allow the PCs to win fights and influence the coarse of battle. It also has basic rules for applying BAD-like penalties for a war zone's overall danger level, which I was really inspired by.
After the conflict, you can roll to determine the after action effects of the conflict, and then where to next. That last bit is provided by the deeply enjoyable Random Conflict Zone table. In two quick tries I ended up with a CR5 Socialist country, temperate in climate, known as Islamar (probably, the People's Republic of Islamar), and Tanistan, a desert Corporate State (CR 4). They're probably neighbors with Latveria and Freedonia.
Overall: This is a good book to fill out the Action line, and I'd recommend grabbing it if you want to run anything like a 20th or 21st century mercenaries game. Good stuff. A quick, fun, inspiring read.