Your statements are conflicting a bit there. You suggest that rules "ought to be enforced by the spirit of the law, not the letter of the law", but at the same time your argument (at least partially) hinges on the fact that the DEFCON argument that Hunk made is not on the wiki/rules page, and then you derive your later argument from a line-for-line analysis of the suicide rule - which, by the way, isn't really correct. The rule's title, "Suicide, Rage-Quitting, and Logging off", does not imply that those three parts are equal or connected in the way that you're asserting. You can commit suicide but not rage quit and it is still potentially a rulebreak; similarly, you can log off without committing suicide and it may potentially be a rulebreak. Also, whether or not you wasted a job slot is not the sole determining factor in whether the suicide is an issue or not - if you lack IC justification, no matter what role you are, it is still a rulebreak and gets handled accordingly.
As far as this specific case goes, however, I don't see a real issue with the suicide. I think if it comes to a point where we're trying to analyze the location and strength of xenos (which is only really tangentially related to the suicide anyhow), I'm inclined to give this the benefit of the doubt. In general, suiciding due to 'pain and suffering' is a little silly and will likely get you in trouble, but I think it was drawn out long enough here for it to be reasonably justified. As far as the argument that it hampers DEFCON goes, I think it's splitting hairs a bit and is peripheral at best. I wouldn't expect players to reasonably consider those sorts of tertiary circumstances, and I don't really think it fits with the suicide rule (in writing and in spirit) anyhow. All suicides hamper DEFCON, so unless we were to apply that logic to all suicides and altogether disallow them - which we're not - it's not really sound reasoning for which to take issue with a suicide.
With all of that being said, the recent trend of people arguing with or talking back to staff is ridiculous and it's something that's going to be clamped down on moving forward. Regardless of if you were ultimately correct or not - as I would say is the case here - if you argue with staff, the ban/punishment associated with that is going to stay. This ban appears to be less about the suicide itself and more about the fact that you were going at it with Hunk in PMs. We have the staff report form for this very reason; you can argue the very points you made in PMs just like you're doing here, without the added trouble of getting into a bout with a member of staff as they try to enforce the rules the best they can. If you disagree, that's when you file a report about it. Even if you weren't in trouble for it and you just disagree with the decision, or what have you, you can always shoot me a message on Discord and we can talk through it. The bottom line is there's avenues to approach a disagreement with a member of staff, and arguing with them in PMs is not one of them. On that basis, the ban is staying, but I will likely adjust the note to reflect that the suicide itself was OK.
Resolved; the ban remains for arguing with staff, but the note will be adjusted given that the suicide was OK.