It's not that unusual for people to date within their friend group in real life, and it was something that occurred quite often in Friends too. Chandler and Monica got married, Rachel dated both Ross and Joey, and Phoebe was left as the only one who didn't have romantic entanglements with any of the main characters.
There are a lot of relationships, both inside and outside of the friend group, that Friends would have been smart to explore. The series didn't take advantage of the chemistry that other characters had, as the writers seemed to have a good idea of their endgames, but it hasn't stop fans from rooting for certain relationships.
Phoebe And Monica
The love and support Phoebe and Monica show each other would be an excellent foundation for a romantic relationship. Their dynamic has always been unique and they could be just what the other needs in a partner.
Monica is high-strung and spends a lot of her time stressing out over the worst possible scenario. Phoebe's optimism can help her loosen up, and the two balance each other out. The only problem is that they lived together in the past and weren't compatible as roommates.
Joey And Chandler
Joey and Chandler are one of the more popular fan ships because of their close relationship. They're co-dependent and hate being apart from each other.
When Joey moves out of the apartment, he and Chandler both take it pretty hard, causing Joey to come home to where he belongs. They even raise a chick and a duck together, making them all one big, happy family. Joey and Chandler are always on each other's side, and their relationship is arguably the deepest one in the group.
Rachel And Gunther
Rachel was always a romantic prospect in Gunther's mind, but it wasn't something that ever came to fruition in reality. It was borderline painful to watch Gunther pine over Rachel throughout the series, as he was always too nervous to speak up.
Gunther was a bit of an odd character, so he and Rachel probably wouldn't have worked in the long run. But after nine years of Gunther being head over heels in love with her, it would've been satisfying to see how this dynamic would play out.
Monica And Julie
Julie was the only person who ever made Rachel feel threatened when it came to her relationship with Monica. Julie was originally Ross's girlfriend, and she and Monica hit it off right from the start.
Ross ended up leaving Julie for Rachel, so there was no reason that she and Monica couldn't give things a go. It might be weird to date a sibling's ex, but since the friends all dated each other it wouldn't be unheard of in the world of the sitcom.
Ross And Joey
If Ross and Joey dated they would never have to worry about getting a good night's sleep. They realize that they sleep the best when they're cuddled in each other's arms, which isn't something that friends usually do with each other.
Outside of this, Ross has always been particularly fond of Joey, even though he's known Chandler since high school. They ended up in a bit of a love triangle with Rachel, but they might have been happier being with one another.
Rachel And Monica
Rachel and Monica have gone down in history as one of the most famous pairs of best friends on television. They always take care of each other, and even though they fight, they come out stronger on the other side.
They lived together for years, and it was because of Monica's kindness that Rachel was able to get her life on track. There are very few people who would be as suited for each other as Rachel and Monica are.
Joey And Phoebe
Joey and Phoebe were a relationship that always seemed as though it was on the brink of something more. Phoebe's crush on him was obvious to everyone but Joey himself, and they were highly popular among viewers.
Sadly, the two never entered a relationship, but it's still curious as to why. Joey and Phoebe got along the best out of everyone in the group, and it felt like they were written to be together.
Phoebe And Rachel
Phoebe and Rachel didn't know each other before the start of the series, but they quickly became close friends.
Rachel is constantly amused by Phoebe, and while other people make fun of her for her quirkiness, Rachel finds it adorable. Phoebe always puts a smile on Rachel's face, and their relationship continued to develop throughout the show. In a lot of ways, Rachel is Phoebe's perfect match.
Monica And Mike
Monica and Mike didn't spend a lot of time together outside of Phoebe, but a trip to Barbados proves that they're a lot more similar than anyone realized. When they face off against each other in ping pong, Chandler even says that "there's two of them."
Monica and Mike are both extremely competitive and their relationship would never be boring. But there would also be a lot of fighting between them since neither of them likes to lose.
Gunther And Janice
Gunther and Janice never had scenes together, but it's hard to imagine that they wouldn't work as a couple. They could have bonded over their feelings for Chandler and Rachel, and although it can't be certain, their personalities would likely mesh well together.
Neither Gunther nor Janice ended up with anyone significant by the series finale, and Friends missed a golden opportunity by not allowing them to interact.