I’m using a book of everything whenever I have time now to skip days. If I have a good stretch of maybe 1 day before the next builder comes free, I will spend a book. I still have one more book from the previous value pack I bought before the end of the season.
Books of everything are really just a wild card book which you can use to skip anything you like. I recommend either heroes, troops or buildings as their primary role, using one depending on the situation at hand.
This picture is just to show how rushing helps me maximize my book usage. Usually if I maxer uses a book, they would not be able to afford any other upgrade without runes. They would need to farm another 10mil or so to start their next upgrade. As a rusher, I can start a cheap upgrade right after using a book for 100% efficiency. It would be painful if TH13 was released and I don’t have my cheap upgrades anymore
Using some weird bowitch pekka combo which is working out great. I’m mowing down lots of bases with minimal difficulty and with heroes alive. Loot is great too if I can find it. Usually I average only around 1.2-1.4mil per hour but sometimes it can peak at >2mil if I get raids like above.