If Pierce Brosnan accepted the role as Bond

To understand the difference is to know what Dalton brought to the films. Dalton was a big fan of the original Fleming novels and his take on Bond was to simply bring the character that was on the page onto the screen. That was his ultimate way of differentiating from his predecessors.

Had Brosnan got the role instead, it's doubtful he would have approached it similar to what Dalton did. However, I think he would have been game for playing a darker Bond rather carrying on what Roger Moore did. There was a period in Brosnan's career where he tried to distance himself from the Remington Steele role after the series was canceled. In the show he was known for being a very lighthearted and fun character, which is probably why people thought he would have made a good successor to Moore. However, his first role after cancellation was to play a cold blooded assassin in the spy thriller THE FOURTH PROTOCOL.

Brosnan has been saying for awhile that he felt he never got a good handle on Bond, claiming he wanted to play it much darker than he actually did, more closer to what Craig is doing. He might have had that chance in 1987. However, by 1995, my guess is that EON wasn't willing to take a chance on having Brosnan play a darker Bond because of the general reaction to what Dalton did. Thus, Brosnan sort of played more of a cross between Connery and Moore. Safe enough for general audiences. Of course, Brosnan would try to inject some darker moments into his films every now and then, but it obviously wasn't enough to his satisfaction.

So yeah, I do believe had Brosnan started Bond in 1987 instead 1995, it would have been interestingly different from what Dalton did and what Brosnan ultimately did in 1995.

https://dejareviewer.com/2013/09/10/last-minute-casting-changes-that-turned-out-for-the-best/

Timothy Dalton as James Bond in The Living Daylights

Who He Replaced: Pierce Brosnan

How It Happened: NBC decided to resurrect the TV series Remington Steele after its star, Pierce Brosnan, was cast as James Bond in 1986. Unfortunately, this cost Brosnan the role of Bond and only six more episodes of Remington Steele were produced before the show was cancelled again. Timothy Dalton, who had been considered for the role as far back as 1969, graciously accepted it this time.

Why It Was for the Best: At that time, James Bond had been played by Roger Moore for 12 years and seven movies. His films had become more comedic in tone, especially 1979’s Moonraker. In the late 1980s, what the series desperately needed was a younger, more serious Bond. At just 33 years old, Brosnan was nearly half Moore’s age. But he was mostly known for his comedic timing. That may not have been enough to differentiate his films from Moore’s.

Timothy Dalton brought a sense of deadly seriousness back to the role of James Bond. Dalton, on the other hand, was 42 and an experienced Shakespearean actor. He brought a sense of deadly seriousness back to the role in his two films, The Living Daylights and Licence to Kill. His second film under-performed in the U.S., but it’s one of my personal favorites of the James Bond series. After that, Bond spent several years in hiatus and in 1995, an older and wiser Brosnan finally landed the coveted role for the quasi-reboot, Goldeneye. We got two excellent films from Dalton before diving back into a little more Moore-esque films with Brosnan. It was the best of both worlds.

Shame it never happened.

Brosnan would have been a perfect fit for the Moore-ish Living Daylights and his character would have gained a lot from playing Bond in License To Kill (and possibly made that film a more bearable watch!).

Pure conjecture this but we can also wonder whether having the bigger box office draw of Brosnan in the role would have lead to a deal being made sooner than the long stand off that occurred between LTK and Goldeneye.

Well I like Brosnan better than Dalton so I think it would have been good.

Brosnan could have been good in TLD, but Dalton being cast was for the better, also Licence to Kill was more tailor made for Dalton, even Cubby Broccoli had stated that The Living Daylights wouldn't have worked with Brosnan as he would have been too similar to Roger Moore and wouldn't have fit the tone, but at least Brosnan became Bond at the right time in '94

Here's a photo of Pierce Brosnan and director John Glen circa 1986:
https://pbs.twimg.com/media/F2N9PwvbUAAm0_S?format=jpg&name=small

https://www.facebook.com/GroovyHistory/photos/a.1707848139525576/2593379947639053/?type=3

It does make me wonder just exactly how close was Brosnan to landing the Bond role before Timothy Dalton ultimately got it?