The Liars were not very likable at times.

OK, so I get that this is slightly controversial. I read the books first, and the way I see it, the Liars aren't just called that because of the Ali-related secrets they keep. Actually, the books have little to do about Ali- it's all about the negative impact Ali had on their lives, transforming them into the people they are today. Hanna was nasty and downright narcissistic in the beginning of the book series. Emily was a whiny girl willing to do anything to see Ali again, while Aria's desire for a more exciting life always left her with less than she started with. Spencer had this sickening need for perfection that drove her to do things some people could never even imagine. These girls were not angels, and could not be defended in their actions during certain parts of the series. In this sense, I think it is much more powerful to have main characters that you dislike in order to get a message across, which author Sara Shepard does stunningly. Although I liked the fact that I could sympathize and relate to the girls in the ABC Family show, to me it just does not fall in line with the premise of this series.

Spencer Hastings and Andrew Campbell were the ultimate OTP.

Yes, you heard me. Toby and Spencer were never even a consideration as a couple in the book series, due to Toby's suicide in the second book, "Flawless." (Note: Toby was an entirely different character in the TV series, and I have to admit that is something I like about the show more.) On the other hand, Spencer and Andrew were in a relationship for a considerable amount of time in the books, and were a fan favorite for many people. Their relationship made them the ultimate power couple in high school, and I shipped them so hard. I would have loved to see this happen in the series, even if it meant sacrificing a portion of Spoby's timeline

On the note of relationships: Ezra Fitz

Mr. Fitz was not a significant portion of Aria's life throughout the book series. Ezra, although cute at first, was deemed creepy and overall problematic early on in the series, leaving a bad taste in every reader's mouth. Aria and Ezra broke up rather quickly, and it was not pretty. So, I was very surprised to see how the relationship developed on the television show. I have the utmost unpopular opinion when it comes to Ezra on the TV show, in which I have always despised him. I really do wish that he was not such a huge part of the TV series, and prefer the message the books sent out when his relationship with Aria did not work out.

There is a lot more suspense and horror within each mystery.

I know this is a heavy claim since it seems that everywhere you turn PLL is unleashing a new bombshell on the show. What I'm trying to say is that there was a lot more of the classic mystery/horror element to the books that the TV show lost over time. Since the show can be all-action, all-reveal at times, inevitably at other times it can just seem to drag out. There is nothing I hate more than getting bored with a television show, and this happens quite often with PLL. The books can be deemed much more captivating and interesting. They keep to a few core mysteries, but within each of these mysteries lies a lot more suspense and horror that keeps everyone on the edge on their seats while reading. I love the intricacy of who killed Ali, which is focused on in the books, more so than the constant switching of A's and good guys/bad gals and whatnot, which is focused on in the show.

The families were more of an integral part of the book series.

I'm not saying that the families of each of the girls are irrelevant in the show, because that is not true by any means. Instead I'm saying that each family had a much different role and their roles fit in better within the entire context of the series. Hanna's mom in the books was nothing like her television counterpart- she was a barely present, careless business mogul who treated her daughter like she did not even exist.

Even though Ms. Marin was less present, her role was essential in understanding Hanna's story-line and why she acted in certain ways. The divorce between Aria's parents was a lot more significant and played into her relationship with her brother, Mike, as well as how she behaved during the series. Spencer's relationship with her sister, Melissa, took up a large portion of content in the books, and was emphasized to a greater extent. Their disagreements were physical, brutal, and downright terrifying at times, which contributes in understanding Spencer's personality and overall family dynamics. Lastly, Emily's parents were a lot more conservative in the books, and their reaction when she came out was a lot different from the television series. Emily's mom was still not very understanding on the show, but the magnitude of her disapproval is greater in the books. This explained a lot more about Emily's personality in the books and why Ali has such a strong influence on her, even when she was not there.