TL;DR Itkovian and K'rul are the same in that they both embody malazan's thesis statement that Compassion Must Be Given Unconditionally Regardless Of Personal Cost (But Without Forgetting It Exists)
let me cook.
K'rul's entire thing was to create the warrens and give everybody access to magic as a way to eliminate disparity, because if everybody can access magic then there's no point in distinguishing mages vs non-mages for example (we know it doesn't work like that but we can't say K'rul did know, originally, I'm talking about his creator's intent towards the warrens). So his warrens are a form of compassion: to help combat discrimination, to have magic be an equaliser.
Contrast that to Itkovian who saw extreme pain in a race and decided to take that into himself so that the grief that made that race different, no longer existed. The Imass could move on because Itkovian took on their grief and pain etc. In this way, Itkovian acted as the equaliser making the Imass "the same as" everybody else, he removed what made them different . It was another act of compassion with the motivation of stopping that grief, so it's different from K'rul's more direct equalising intent, but Itkovian was still moved by compassion and he still made things (more) equal through his actions. Or that's what his intent was, at least.
And there's also the fact that their compassion came at a big, indeed a *HUGE* personal cost, but the books reinforce the fact that compassion is needed and good always, without shying away from how much it can take from someone at the same time. Both Itkovian and K'rul are perfect examples of this. People quote Itkovian's monologue about compassion ("we humans do not understand compassion....") and with good reason! But K'rul is just as central a figure to that thesis statement
(we could delve more into whether K'rul and Itkovian were successful, but I don't think that's necessary to make my point because malazan's thesis is that Compassion Is Necessary Regardless Of Consequence/Personal Cost, and both K'rul and Itkovian embodied that with their intent)
















