Not bitchy at all! I'd rather feedback be honest and constructive rather than people paying me compliments out of obligation, so we're all good. You don't read like a nightmare reader but you're absolutely an outlier in general consensus thus far, but that's why I find these kinds of insights fascinating as they're typically free from any kind of bias. Funnily enough, Path D is meant to feel uncomfortable as a whole because of what's going on. Picking up on Tyson's abusive behavior towards Dave is something that very few people actively enjoy, but as a whole people hit that sweet spot of "Oh no, things are bad" without having the same reaction you initially did.
Reading your revised reactions to Path D, it's given me some things to immediately work with although a lot of it should be tightened and tidied come the editing phase. Hopefully at least. It's clear things aren't resonating as strongly as they can be, and that falls on me to bring that across better. Maybe not to the extent of creating ego bleed (which is why making Dave his own explicit entity as opposed to a self-insert, semi-blank MC), but better? Absolutely.
It's interesting you note what kind of visions Dave has about his father as the intention was to handle Dave being haunted by how he remembers his dad as opposed to actively reflecting on various things they did together. That's at the moment planned for later now that the barrier of him accepting him as gone has been breached. For the most part, David is well received at least in the more vocal circles of the fandom for two reasons: He's a hotter, daddy version of Dave; and/or "I wish I had a dad like him". I haven't run an analysis on family dynamics for furries but what I have noticed is that the father/son bond as a whole is somewhat lacking. So latching onto a surrogate, idealized father figure is probably helping his popularity. As for Dave, who had a stellar relationship with his father, is meant to read as suffering in not knowing how to process the fact that he's now gone, mostly in part to not wanting to admit it's the truth. His friends are also garbage in actively helping him come to terms with this as well (as evidenced by their lack of progress since it happening and no steps taken at all on Path C/D), but that in and of itself was meant to be a life lesson that your friends aren't out of obligation your therapist. Support circle, sure. But not a replacement for professional help.
This kinda flows into the intention behind Dave's depression. There's more there to be covered later in-game, but Dave being depressed wasn't really meant to evoke sadness or really any other emotion aside from worry, concern or maybe dread. It's there, it's yet another obstacle to overcome (much like using the vault although now it's Dave at risk). If someone was to feel sad about Dave being suicidal probably lacks world experience with the topic which they should be thankful for missing if it makes the nuances a little hard to get. The bigger worry should be triggered when he doesn't bring it up with his friends.