The geniusness of DS1 level design is not just in that it's interconnected. It's also the vibe, the way it makes you feel. Darkroot Garden/Basin is not exactly the avatar of complexity but the vibe is awesome.
Plus all the secrets, hidey holes and hidden details - tho they've overdone it at places. I hate that you can discover many things only through a sheer accident if you don't look at wiki or messages (for me messages have been the most hateful feature throughout the series). Sooo many times I thought to myself "How the FUCK have people figured out THAT? Fuck you Miyazaki".
Three most brutal examples:
- those two hidden walls in Blighttown. Are you kidding me? Maybe (big maybe) a few crazy completionists that poke every wall they see (what a fun way to play the game btw) could find the first one but the second one behind the chest? Jesus. And there are TWO big areas hidden behind them!
- in my first blind playthrough (offline) I never figured out how to get to enter the DLC I paid for and was looking forward to. When I killed the hydra I ran around mapping out the place. I discovered the cave in the corner but it was empty. I thought "huh, another unfinished nook...whatever let's go on". Never EVER it occured to me to go back there. Because obviously the golem spawns only after a loading screen. Very clever From. When I finally stood in front of Gwyn's fog door without ever coming across the DLC area I thought I
could run through all the areas again, check every nook and cranny but I couldn't muster the strength so I checked wiki.
- I never got back into the Asylum. I found the nest, curled like a ball but after a while of nothing happening I thought maybe I'm missing a quest item or some such. Got all the way to Gwyn without finding it obviously. Because it's a great idea to have players wait 15 seconds or so before the cutscene kicks in (same with the Gravelord covenant). So it's another two areas I never entered (second Asylum and Ariamis).
I love the quirks and secrets but this is way too much. I basically never found a good third of the game (well I did but only after checking the wiki). DS3 overfixed it by stomping out everything remotely quirky and interesting and secrety. I'm not saying you have to find everything on your first playthrough even if you just blindly stumble forward without paying attention. But give players a chance ffs.
And despite all of this it's still the best game ever made.