DS3 is smoother and more polished, and the linearity means you don't risk going Catacombs or New Londo first, that's true. But I think DS3 gets hard way before Irithyll. All the bosses are harder than anything in DS1 and Iudex Gundyr could be a roadblock right off the bat. (Oh I forgot to mention, I really liked Champion Gundyr too as a boss.) Anyway I guess Asylum Demon could be a roadblock too if they don't realise you are supposed to run past him at first. But the first couple of areas really aren't that bad. Take it slow and keep a shield up when you round every corner and you'll be alright through almost all of it. The only real problem I see early on is Capra Demon. I guess the basilisks are a bit of a gotcha.

I personally found a lot of challenges in the early areas of DS3. Felt like there were lots of roll catches and annoying enemies, like the Lothric Knights. Road of Sacrifices into Farron Keep felt like absolute ass and were awful areas, those crow enemies were hard to deal with and unfun to fight, and likewise the jumping goats in Farron Keep.

If by monster bosses just oversized bosses count then I can get behind it. There are several that come to mind where you fight the camera more than the boss and get hit by things from offsceen while exasperatedly yelling "I can't fucking see anything Miyazaki!" at the screen.

Sister Friede was just incredibly hard and also having incredibly long Phase 1 and 2 which made trying to learn the difficult Phase 3 take forever and felt like just disrespectful of my time. Felt like every attempt would take 10 minutes to get through the first two phases only to get one-shot instantly in phase 3. Absolutely hated it.

If even you can't beat Midir I might just keep postponing it. I still have my save lying around but it's been a while and I'm kind of on a Ninja Gaiden kick at the moment as difficult games go.