Better main leads

I like this movie, in spite of its massive flaws, chief among them being the MOST MASSIVELY MISCAST LEADS IN THE HISTORY OF FILM!!! The theater audience actually laughed out loud when the spindly Laureline punched out a grown man, and also when she did her runway walk in the giant hat. It's such a frustrating movie, it could have been absolutely great with some minor tweaks and better casting, and it's too late to fix it now.

For casting better Chris Evans than Christ Hemsworth, Hemsworth isn't much of an actor except when he's allowed to be funny, but Evans can take a badass role and make the character likeable and vulnerable, as well as a believable badass. Not sure about Laureline, it's not exactly a demanding role, they just need a tall fit attractive gal to be Valerian's foil.

Although I don't think either of the leads did a great job, and Cara D is fundamentally lacking in charisma, I do commend the filmmakers for looking beyond the typical bland heroic types, even if it didn't come off on this occasion.

I'm tired of seeing the same people play the same types of heroes in genre movies.

They should've cast Mel Gibson and Danny Glover. Sure it would've changed the dynamic of the story quite a bit. But wouldnt it have been a blast?

johnny depp and amber heard when each of them were 20

I'm going with Chris Pine.

Seems like a safe choice but as another commenter mentioned, he's not overbearing or over-powering as an action lead, and he definitely has a bit of that tortured charmer going on, which would have been necessary for a role like this, following someone who has seen a lot and done a lot and has just enough of a chip on his shoulder to be cynical yet hopeful. Pine is perfect for that role.

Someone mentioned Hemsworth, but he's just not right for portraying someone who uses being glib as a facade, which Pine does perfectly. Also Hemsworth is a little too large for life for the role, which needed someone a little more everyman, and Hemsworth is definitely not that (which is why he was perfectly cast as Thor).

Chris Evans is a little too... contemporary and dandy for the role. People will point to Captain America, but in many ways it was his boyish charm that helped sell him as the Cap. Here, Valerian needed to be only slightly world-weary (or galactic weary) but also charmingly witty and astute. Evans portrayed something somewhat akin to that in Sunshine, but it still wasn't quite the fun-loving playboy that Pine mastered in his portrayal of Kirk in the Star Trek films. In fact, despite his boyish charm, has Chris Evans ever played a convincing playboy in any film? I can't think of any.

Baring that, a foreign-born star could have been good for the role... a young Ewan McGregor would have been perfect for the role, or maybe David Tennant?

I don't particularly like him but James McAvoy seems like he could have pulled it off.

As for the female foil? Definitely Karen Gillan would be my first choice. Baring that, Niamh Algar or Elizabeth Debicki (but you'd need a tall leading man to match Debicki's height). A bit out of left-field, though, I think a Spanish or Italian actress probably would have been a better pick just to add some spice to the role, like Barbara Opsomer, who could have been great if paired with the right male co-star.

I literally just commented on another post about mediocre leads.

Dane & Cara kinda "ruined" my enjoyment of the film. They were horribly cast.

Better leads would've been more fun to watch imo