Critical Hits in Souls (or to be more accurate, lets just call them finisher/mercy/execution whatevers, because they do not share commonality with the wider definition of critical hits) are achieved by attacking a poise broken or parried enemy or backstabs.
They distinctly are not caused by executing a particular combo. And with the exception of backstabs, have no care for positioning of any kind. PArries are literally the Assassin Creed/Arkham counter minus the prompt (or well, I guess we could say the Assassins Creed 1 counter which had no prompt). As the Souls series has gone on, they've also been ever-increasingly reducing the options for these with non-parriable attakcs and backstab immune enemies. By the time you hit Elden Ring (which added other ways to get crits), they've actually niched down to only making sense to use for 2 weapon classes, every other weapon does more if you ignore the crit window and keep mashing.
The four total status effects in Souls (and being generous to count Toxic/Rot and Poison as separate) are all flat DPS effects. You get damage over time, damage burst when the bar fills, or damage burst when the bar fills + brief window of bonus damage. Not unique to Souls by any means (Salt and Sacrifice for instance, features equally silly Fire/Poison/Ice/Spore status all being generic DoTs (light makes things easier to stun, I have no idea what Dark or Dragon damage does). But its a veil of pretense to consider them anything but another DPS build, especially when the method of applying status in Souls is exactly the same as the method of doing regular damage.
Status effects in general are very tough to actually apply meaningfully. And with Souls being very focused on making it awkward to use things in tandem (one spell or item without fiddling around with the bars) it misses out on most chances for interaction. Whereas other games will often have quick wheels, or even Warframes R1+face button to quickgrab a spell/ability from 4 options. Most of the ones that allow for more complexity are based on interactions either between statuses and other effects, or with the environment. Where you have crossover effects like Bioshock/Dying Light/Path of Exile's get the enemy wet then hit them with lightning (or cold as well, in the PoE case) effect.
As far as it goes, I don't think Souls aspires to be a build-based game. Its possibly the weakest aspect of its gameplay formula, typically being a one note "Focus on this stat for the particular brand of hitting stick you prefer til it hits 40, then just alternate HP/STam, maybe do a bit of the latter beforehand if you find yourself strained". It definitely falters in much player choice or interaction within the story to really fulfill the other half-slab of what we'd define as RPG. Its prettymuch left to being a third-person action game, and the vast majority (or well, in the prominent space) others in that genre have deeper mechanics with higher skill and difficulty ceilings (though not all apply them fully. Zelda has never exactly pushed you to the limit of using multiple abilities in tandem despite having all those additional mechanics present)