DS2 is very polarizing. Miyazaki didn't work directly on it and personally it is my least favorite. However it is still a phenomenal game and I wouldn't recommend you skip it. It has the best weapon and armor variety and introduced an incredible dual wield mechanic called power stancing. The DLCs each have really brutal sections so I wouldn't hesitate to coop them if you don't want the challenge. The biggest issues (imo) with it are that the world isn't built at all as cohesively as the first dark souls and that there are lots of ganks (enemies randomly attacking you from hidden places or far away). Also the bosses are not quite as diverse as other dark souls games.

I definitely think HK is harder than DS1, especially with the DLCs. It's really not all reflex based, especially if you use a shield and heavy armor (which is a completely viable way to beat ds1). Some of the HK fights are fairly technical like you mentioned and the DS series overall often provides that same "if I just did things right I would win" feeling while dying over and over. But DS1 is an amazingly built world with a lot of emotional connection to NPCs that feel much more organic than plenty of other games. Some bosses are challenging, sure, but it's not as technically difficult as the later games in the series.

All that said, I would strongly recommend the game. And once you beat the first you might just find yourself wanting to continue the journey through the other 6 from software games in the same spirit.

Why would it being like DS turn you off? HK is an amazing game and its actually what got me into DS.