Taking a look back at the actual history of the genre of thriller is somethign really important. If you study enough history, you are able to learn from past mistakes and learn from great success. There is no problem with borrowing ideas from past movies, if they succeeded then ofcourse you will want to learn from it. Thriller is dated all the way back to 1923, which this way there is a lot of content that one can learn from and create something great. The website http://www.filmsite.org/thrillerfilms.html has a pretty good overal history about the genre of thriller which again is a great way to study up on great hits of the  thriller genre.