Who is your strongest character?

I think mine had to be my mage Jyoti Gehen. She had no problem with hard, but necessary decisions, which cost her two friends and some sympathy.
Most of my other characters want to be liked, which can be a weakness.

DD Hawke for me. The man could mow through enemies. That said, both my Warden and Inquisitor are SnS tanks, so their job isn't killing. I would say that of the tanks, my Inquisitor is the stronger of the two.

I'm good at playing mages, so mages are my strongest class in every game. I played rogue and 2h warr Hawke where Arishok fight was a pain and I died so many times. My force mage obliterated Arishok without him having a chance to reach her.

My Arcane Warrior is the only class where I had luck taking down nightmare Harvester too.

I'm terrible at playing rogues, so it's my weakest class. However, I've currently began a playthrough with a DAI rogue dwarf. This is the first DA game where I can take advantage of stealth. But, she's level 4 so it's too early to tell if I'm any good at this class, but I am finding DAI rogue a lot more enjoyable than DAO (which was the worst) and DA2 (where I liked that teleport backstab move but it was a big pain anyway).

Physically strongest? Niall Hawke.

Martially strongest? Darian Tabris.

Mentally strongest? Morgan Trevelyan.

Of my canon worldstate, I'd have to say Hawke would win in a straight up fight. She's a DW rogue that fights more like a dual sword warrior. She grew up on a farm, so she's got the strength and toughness - definitely has the physical strength advantage of the three. She might not have been a mage, but she still learned how to defend herself against magic from her Dad, as well as sparring with her warrior brothers - so she used to fighting against different type of opponents.

Warden Tabris (dual wield dagger rogue) is a bit of a wildcard. She's not as physically strong as Hawke, but she's faster and probably more agile. She embraces the shadows and her husband's assassin training, so her strength is more in the quick sneak attack than toe-to-toe combat. Also, her idea of a "fair fight" is one where she lives/wins . She's a tough badass in her own right, but wouldn't be able to beat Hawke in a fist fight.

Inquisitor Lavellan would lose without a doubt, lol. She may be a very strong mage and Knight-Enchanter, but she is not a battlemage (her strength lies more in healing and support). She's the least physically fit of the three and not exactly the epitome of elven agility and coordination Although she would probably be the last woman standing in the political arena....

(Going by the characters themselves, and not as much by game mechanics.)

It is one thing to ask which of your Wardens is the strongest Warden.

And quite another to ask who's the strongest in the Warden-Hawke-Inquisitor trio.

I will flip the coin. The coin says my Arcane Warrior Warden is the strongest.

Yeah it's hard to tell really but I tend to make shorter work of my enemies with my  mage heroes than other types. But then that's probably why I enjoy playing them most as well.

Probably the arcane warrior I had my Orlesian Warden be for DAA. She basically made chunks of everything without flinching.

I feel like I have too many characters, and they're all strong in different ways. My Warden Aeducan has a tactical mind and high survivability, my Brosca has been scrapping and sneaking since he got out of diapers, my Hawkes tend to be extremely powerful elemental/force mages with some martial ability, my Inquisitor Adaar is built like a brick house and - at least for a while - has the Anchor supplementing her Rift Mage abilities.

I feel like Hawke is the most powerful by a narrow margin, though that could be Varric whispering in my ear. And it still won't do him/her any good if Tabris or Brosca go to shanktown before the spells start flying.