(The recommendation is just a formality) Yes, I have 100%ed the game
Outside of challenge mode: • Too much RNG (especially in the form of health and chests); Tier system is very badly done • Variation is extremely limited when it comes to rooms and bosses • Many items are completely useless and even good players get gimped if they don't get at least one decent item in a run. The game seems to want you to collect as many guns as possible and switch rapidly between them, but most of the time you're sticking to one or two guns and hoping you can sell off the rest to a sell creep • Movement is extremely slow (even rolls), and there are very few items that can speed up the game. This is a more of a nitpick but it does make everything outside of the bosses feel slow most of the time. Teleporters definitely remedy this to some degree but it's still there and can leave sections of "downtime" where you're just running inbetween rooms that didn't have a teleporter near them (those obnoxious hallways that connect each room are especially bad). This is why most runs are ~40 mins long, which feels like an eternity when you're encouraged to explore each floor in its entirety • Larger rooms in general are almost never as satisfying as smaller ones • Very few items work well in tandem with each other, and in the rare occurance that they do the bonuses/ extra effects don't give much of an edge to the run • The bullet is an insanely broken character that you'll most likely spend 90% of your time playing as after you beat the past with everybody else • Farming hegemony credits is pretty stupid • The benefits of getting cursed are not nearly enough to outweigh the downsides. It feels like something the devs left as a footnote for players to challenge themselves and not much else • There are no benefits to taking the harder alternate paths the game offers more than once, as they are only there for the purpose of one or two unlocks. This is especialy true for bullet hell, which becomes pointless after you have unlocked the riddle of lead. After that, they only serve as extra challenges, just like with curse from the start --> (To clarify: I am not saying areas need infinite replayability, but only having to complete a side area once with a single character for an achievement pales in comparison to giving a bonus to players who choose the "harder path". In the case of bullet hell, giving a unique unlock for each character would be a similar fix. This would add to the challenge of the game, and make the bullet less of an "easy clear" character)
Challenge mode: • Many modifiers/ combination of modifiers are completely unbalanced or downright unfair (Ex. hammer time/ zone control, gull's revenge/rat's revenge in a room with only platforms): This is especially true for bosses. Double challenge mode only makes this worse, I imagine • Some modifiers can be completely negated by items or feel pointless (Ex. high stress in early rooms, poison trail getting negated by sponge or hazmat suit, and cursed ceramics in general) • Wallmonger feels like an impossible fight to no-damage unless you have an insanely broken run • High dragun is not only a DPS test here, but also a blanks/ invincibility test. Certain moves or combinations of moves are impossible to dodge normally, and his knife familiars still have a bit too much health. His second phase can also be near impossible unless you get a good circle pattern/ have speed boost items. Add high stress to all this and you have a fight that feels artifcially difficult rather than a legitimate challenge
Overall, despite how much I have come to hate it via challenge mode, gungeon has a slew of good ideas which, with some tweeks and changes, could result in a far more enjoyable experience that would take a far longer time to go stale. At the moment, the joy of beating bosses and getting better is definately there, and past portions are very well thought out sections that add a bigger reward for completing the game. Though it falls flat more than it shines at the moment, the "upcoming DLC" could change some things for the better, as the devs do seem to be actively looking for what people are talking about/ what they could be changing.