This game does have flaws, but I don't think that they've yet been mentioned in this thread.
Those who are saying that there is a design decision that you don't like, and that your statement that you have found "huge flaws" is an exaggeration, are correct. It's not that big of a deal.
I like that the upgrade fights are unknown difficulty. Loading times are SUPER FAST in this game, and I like to be surprised. In the Adventure mode, your character could spy on the enemy troops to see their composition - but if he's about to enter a weapon's realm, how would he "see" what's lying in wait? It's just more exciting that way.
My only real complaint about the game would be that, compared to previous games from this developer, it has just a few less surprises. For example, those who have played Space Rangers 2 will know that all sorts of little mysteries could "hit" you at any given moment, and that certain bonuses or upgrades could be achieved by following long and seemingly unconnected quest lines or by doing a lot of far-flung exploration. More of that in King's Bounty would have given it much more replay value. And I would have loved to see a return of the text-based adventures that were available in SR2. But for the first game in a new series it is excellent!
This game is not really an RPG. It is a turn-based strategy game with RPG elements, just like the first King's Bounty. And that's okay - it's nothing bad, unlike being a FPS with RPG elements that steals the name of a brilliant RPG and adds "3"...
Nevertheless I think that this game is very good for playing Iron Man mode. You have to be very good and very cautious to survive playing Iron Man mode, or you will be dying and restarting the game. Isn't that the point of Iron Man mode anyway? How would Iron Man mode be rewarding if it was easy to never die? By playing Iron Man mode you are making the decision to play the game with a high chance of being forced to restart, that's how it works.
Anyway, I hope that when you talked about playing Baldur's Gate, you meant the real Baldur's Gate games and not the recent hack-and-slash junk.