Awesome news, what seemed impossible is starting to look not-so-impossible.
I'm currently playing in NG+, and I still use the black leather armor that my thief started with (but upgraded to +8 and +9).
My main weapons are:
Priscila's Dagger +5, Dragon Crest Shield +5 and Black Bow of Pharis +10
My secondary weapons for special occasions:
Queelag's Furysword +5
Lighting Estoc +5
I just rang the second bell and I'm not encountering too much resistance so far, even though I take massive damage from the enemies in this NG+ compared to the first playthrough.
The player experience of knowing how to fight each enemy is what really makes the difference in this game, I don't find it specially hard or frustrating like many others say, but what I do find is that each encounter demands awareness, discipline and concentration from the player, and that is what makes it so good and rewarding, you can't just mash through everything without paying attention because the game will punish you hard for trying to do that.