Me? Typical background for a 50+year old ... rated ~2199 30 years ago and ~1999 now. No time for extended study chess or tournaments. Play maybe one otb tournament every year or two so face the age-old question of how to best prepare for a big summer time tournament given rust.
Well I agree that tactics is the key. Five years ago I won an amateur section by going through Reinfields 1000 combinations' book (took me over six months). I picked this book up as I aim for another summer tournament three months from now. As for what I look for in a book on tactics, it is something for 30 minutes of practice/study during my commute on the train, and puzzles/positions not too profound or basic.
At the time of this post, I've finished most of the book except for the examination --- I have a favorably opinion of this book. Do have to mention that I have picked up other books on tactics ( Chess Cafe Puzzle book, Charles Hertan's book, among several others ) but did not finish those. So my approval barmoter is completing a book from cover to cover --- and like many chess players, I don't complete many chess books.
The format of the book has annotated examples exempfying the tactical theme in each chapter, followed by solve-it-yourself positions, and lastly, a section for the final examination. As for the level of difficulty ... the positions were never too basic, and got progressively more challenging. The author took care in selecting the positions ... first few positions are the obivious "look for the theme, look for the king, look for check" kind, but then it got more realistic with positions requiring quiet moves, and then as positions having holes and defenders' resistance.
Again, enjoy the book so far and give it a high score.
Given my preferred reading pace, might take one-to-two months to finish.
Cheers,