I wouldn't call the fire longsword this game's Drake Sword, it's not nearly as powerful. By the time I found it my upgraded regular longsword already did more damage to most enemies, since weapons with 2 damage types have to get through 2 different defenses separately after all.
(number of attempts in brackets):
Forest of Giants
The Last Giant (3)
Old Dragonslayer (2)
No Man's Wharf
Flexible Guardian (1)
I'm now at the point that I can use my first miracle (Force), but am still pondering if it was worth the hassle or if I should have just kept on increasing my combat related attributes rather than pumping tons of points in attunement to equip at least one miracle. Well, if everything else fails I can still respec I guess
No Man's Wharf was quite fun and it's an area that's much easier if you're careful and make deliberate use of ranged weapons like a bow. I didn't die a single time there, only time I died was when I fell into the water where I thought I found a shortcut. Not making that mistake again
I have the fire longsword as backup weapon, but for most enemies my regular upgraded longsword does more damage. I also found a greatsword but it's a bit too heavy for my equipment load... don't want to get rid of armor just to wear that.