Trying to get caught up here (both on the thread exchange and with the facts of the incident itself as I hadn't looked at it or thought about it in some time) and will provide some input ASAP.
Also, who'd have thought 15 years ago you may have actually wanted my opinion on something some day?
So after reading the thread, after reviewing some online articles about the incident, and based on my memories of the videos, I'll say the following:
1. Criminal law is very jurisdictional-specific. I am not licensed in Wisconsin nor do I know any of its unique laws related to this issue. I can only approach this from the perspective of general criminal law principles and the hypothetical of if this happened in my jurisdiction.
2. While it is not that difficult to obtain an indictment (see: Andrew Thomas and Sheriff Joe indicting Maricopa County Board members and the current indictments against the protesters in Maricopa County), it would be fair to say that there has to at least be some evidence to suggest that a reasonable person could conclude the defendant committed the act(s) alleged (i.e. probable cause). So I find it hard pressed to say that it would be "delusional" to think a conviction is possible on some count in the indictment.
3. In my experience, the state will make a plea offer in over 99% of cases. Now, there is no right to a plea offer and certainly no right to a favorable plea offer. But I would expect one to be made here after lengthy discussions within the particular prosecuting agency. There are often many factors at play in plea negotiations that can dictate the outcome of the offer that range from sensical (e.g. proof issues, suppression issues, meaningful/impactful mitigation, quality of defense attorney) to the borderline frustratingly unfair (e.g. luck of the draw with the particular prosecutor, some external pressures, the court's calendar, a particular judge who is quick to reject plea offers, etc.).
4. The decision whether to accept a plea offer is left entirely to a defendant. In other words it's nonsensical, unless the speaker knows Rittenhouse intimately, to try to make a statement such as "it won't plead out if homicide is included" or something like that. Now, ideally, the defendant makes this decision upon listening to the advice of counsel - but ultimately the decision whether to accept a plea agreement rests solely with the defendant and, of course, defendants are not always rational.
5. Based on the charges I find it unlikely that a plea agreement to less than, say, ten years will be offered. I say this because there are three victims and prosecutors generally have some duty to listen to victim input. As such, I cannot imagine any of the families happy with a dismissal of the charge associated with their particular loved one and, therefore, it seems likely than any counts will be dismissed and/or run concurrent to each other making it a practical challenge for a sentence of only a few years (note: Wisconsin's sentencing scheme may have something unique here that I don't know that could change my line of thinking here). I say this as I currently am working on a double-homicide case with some significant mitigating factors yet I'm running into these challenges in plea negotiations. Put differently, when there are dead bodies that people care about, the state is not likely to be willing to "deal" like they would in some other cases and may simply be willing to go to trial and risk losing on some of the more serious counts rather than run afoul of victim input or lose credibility of a judge who may reject the plea agreement.
6. Analyzing the case for self-defense, we have to remind ourselves that there are three victims here. As such, it requires multiple analyses. As others have pointed out earlier in this thread, the use of deadly force is limited to situations where the imminent threat of proportionate deadly force is reasonably deduced by the defendant. I imagine Wisconsin, through either its statutes or through case law or some combination thereof, has some particular jury instruction on this issue for the jury to consider. I will say this, as it relates to self-defense, when it's a defense that I assert with vigor usually the corresponding prosecutor will cease plea negotiations. The reason this happens is because, unlike mitigating circumstances (e.g. heat of passion, some mental defects, etc.), a self-defense is a claim of actual innocence. Therefore, usually, a prosecutor will feel uncomfortable negotiating with somebody who is affirmatively asserting actual innocence because there could be an issue with the allecution. Now, this isn't to say that it never happens (and as a defense attorney my job is to try to massage this sort of situation and craft a factual basis both sides can live it), but in my experience prosecutors may not negotiate as much as they would in a true self-defense situation.