Thrillers can, and usually do, have sub-genres that sometimes make it hard to pick one main genre. Most Thrillers have mystery and suspense all throughout the story and vice versa. I think the ones that stand out for me the most are the crime, psychological and horror. Crime usually includes what I've mentioned above. Psychological thrillers include Malice by Rebecca James (which also falls into YA), In The Woods by Tana French, Along Came A Spider by James Patterson, Odd Thomas by Dean Koontz. Most of which I've read and recommend! The Horror Thrillers are interesting and probably stand out the most for me. The Face by Dean Koontz, American Psycho by Bret Easton Ellis and my favourite by far Afraid by Jack Kilborn.
These are genres to check out and read if you haven't done so already. There will always be one that's suitable for what you all like more often than not.
blog: Spellbound by Books
Thank you Melissa, I'll take some notes and add some of these titles to my TBR list, I'm always up for a good thriller :-)