Sometimes we need perspectives like these to remind us that it isn't always so intuitive from day 1. Even those of us that went into DS1 from Demon's Souls learned most of what we needed to in that particular trial by fire in 2009/10, so coming in fresh comes with a big learning curve. Souls isn't like anything else, for better or worse. It's why it influenced so much.
- Equip weight always favours light rolling (<25%) (DS2 onwards buffed medium rolls to make it a very wide ranged of "normal"). You aren't told this, so if you start with a class that weighs you down then you're crippled because you don't know any better. Every time I start a new character in 1 I strip off without thinking because I'm so used to it, but even ER will start you off fat rolling despite how crippling it is to the gameplay. Souls gameplay is stamina, attack commitment, and dodges. You can't cripple one and expect people to have a balanced time, because shields aren't always the best way to go. Maybe at first, but that fades.
- The parry mechanic takes some learning, and I didn't touch it in my first playthrough. DS1 has the easiest parrying looking back, but that doesn't mean it's intuitive by default.
- I don't know how it would be improved, but we all know deep down that the item/spell selection is wank. Eventually they later added a long press to go back to the first slot and ER added the 4 way quick items, but items/spells are still a slow, linear cycle.
But to speak in the series' defence as a long time fan, once it clicks then it all begins to make sense.
You get to appreciate how to approach combat and what they're doing (including the speed and the stamina), and those rules see you through the entire game.
Then you get to appreciate DS1's world design, which thanks to the interconnected nature of the map is the best in the series.
Then you get to appreciate the lore (if you want to). I find the Souls games are better once you know how to play them, for example the fat roll thing.
DS1 is by and large the fairest game of the series, and although it's 11 years old and looks like it, and is flawed in the end-game, I would still recommend it. Later games improve aspects as you would expect (UI, aforementioned medium rolling, etc) but they also added Bloodborne's speed but without the things that make Bloodborne what it is.
On a personal note IC, PM me if you decide you want to try DS1 again and I'll happily pass on any relevant wisdom.
On the wider topic of DD, it does remind me how much I miss the tail cutting mechanic from DS1. It added something to bosses that was lost in future games, and that's a real shame. It was never as influential on bosses as it is in DD, but it added both a reward and a dynamic element that is no longer there.
Very much looking forward to DD2, I hope they get it right. I wager we will see a lot of people making threads with the same opinion as OP when the time comes, and it's entirely fair.