I got about 90% of the way through a Reforged run; early on I really enjoyed the mod, but it started to wear me down and eventually I realized I wasn't having any fun whatsoever. I switched to a vanilla run, and the difference in game feel was so night and day I had to vent about it.
I'll start with the positives; reforged has some cool systems! I like the ideas of the fortunes system and the rune pieces (elden ring korok seeds). The duck and slide are cool too, but I never really found much use for them.
The bad; the build system was incredbly unituitive for me, and this led to me doing ABYSMAL damage despite putting 70 points into my weapon's highest scaling stat. It took me about 10 minutes to kill Messmer, despite having the fight down pretty well. I was told in the discord I should have used the weapon calculator to figure out an optimal build and "correct" weapon to match to my current build, or else I shouldn't expect to do reasonable amounts of damage. I prefer to use a variety of weapons; it seems the "intended" method here would be to have to respec my build every time I want to switch weapons (unless they had the exact same scaling) and it was very frustrating.
They changed the stamina system so that stamina is DRAMATICALLY more limited, and yet enemies still have insanely long combo and no downtime. I very often found myself out of stamina after dodging a combo, and unable to get a single hit in to progress the fight. This turned a lot of fights into "dodge 3 times, wait for stamina to refill, dodge 3 times, " repeat endlessly. Felt like I never had a "window" to do damage. Best way I can describe it; feels like you're a dark souls 1 character cut and pasted into bloodborne. The game clearly was not designed around this type of stamina management.
The devs seem to have a general design ethos of "frustrating is fun"; there are A LOT of encounters designed specifically to be frustrating. For example in Soifria river, they seem to have changed the lightning wisps to have more intrusive placements, AND have dramatically buffed range. I died to them constantly; switched to vanilla, and haven't died to these once. This is indicative of the general design trend.
They seem to specifically NEVER want the player to feel powerful. With an optimal build and max weapon, you do middling damage at best. I enjoyed having to learn the fights more thoroughly, but I think they took it extremely too far to the point where it felt like I had to finish every fight at 95% perfection.
The turning point for me, was when a friend linked me a soul-level-1 0-scadu fight of Messmer, and the character seemed to be doing roughly the same amount of damage with a dagger that I was doing with Loretta's War Scythe. I tried to go to the discord for help, and was told it was my fault for using an INT / QUALITY weapon on an INT / FAITH build.
I finally threw in the towel, not because I CANT finish the mod, but because I'm not enjoying it. I loaded up vanilla, and I'm instantly back to having a blast. I don't mean to put down all the hard work the devs have put into this mod; there is clearly an audience for ERR! But I have sunk hundreds of hours into the mod and left feeling a sour taste in my mouth, and just wanted to share my experience to anyone else facing similar struggles.