I always thought Gwyn was really hard until I learned to parry him. Kalameet was hard, but the fight was so fun that I didn't care. I actually used to consider Gaping Dragon the easiest, since it's easy to lure and damage. Of course, as I played more playthroughs I realized just how easy Pinwheel was.
I'm confused. I thought people hated microtransactions. As a mod author: this sucks. If you're making mods for any reason other than to give back to the community then you're making them for the wrong reason. I'll allow an exception for large-scale, hugely time-consuming projects like Nehrim, but not for a sword. You should probably re-evaluate your situation in life if you think you're going to make any considerable amount of money creating mods.
It should be perfect for you. DS2 was never hard for a Souls game, so the ramp up doesn't mean much. Take that with a grain of salt, though; you're still gonna get your ass handed to you by a few bosses and areas.