When is it better to go through hearts of stone? (The Witcher 3: Wild Hunt)

in theory after, because it is higher in complexity

In general, the difference is insignificant, several events / options will change, while they will not affect in any way. But the developers said that it is better to go after the main storyline.

Yes, how many of these themes are there to create ... Is it difficult to climb in shape? =) In the game, and purely KS are slightly different options. I personally like the game more, both logically and for some limited interaction with the characters from the add-on and the plot. Also - in the game, thanks to the addition, you can use different chips - the Master of the Runes is the same, additional armor and swords. It makes sense to go through the add-on completely separately only if there are no saves at all, and the crowbars from the beginning of the game (since at least some kind of add-on can only start from level 10, and comfortably from 20). If there is a save, then who prevents the add-on from being included in the whole game?

thanks for the answer

JUnnAmmED
Che for nonsense .. Where then the dialogues, with the same Vesemir about his girlfriend, or with sorceresses about the sign on Geralt's face?

Stribogg
Spoiler
If you haven't passed hearts of stone - don't open the spoiler!
Spoiler Well, for example, about what you tell Vesemir's ex-lover about his fate. About additional chips, in the form of cool weapons and a rune master, I think there is no need to talk about. And yes, for the attentive: the difference is insignificant

JUnnAmmED
I talked about what advice from the developers can be to go after the plot, if they also inserted some dialogues into the plot regarding the add-on, and in the add-on the same dialogues change somewhat depending on how things are with the story line ... Why should I spoilers to write, I already played the game, and the COP passed 10 times probably =))

Well, DLC is generally best done after the storyline.
For they leave, respectively, after the release of the main game.
(Well, maybe not always. You never know in which DLC game it is better to go before the plot. (Actions there take place before the main plot, for example.)