So...I did a LOT of research and observation on the upper blast line in "Smash 4" and especially "Ultimate". And let me tell you...it was torture! Some bad news (more bad news for me, but I'll explain more on it).
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Calculating the upper blast line's RNG, as of "Smash 4" and especially "Ultimate", upper Blast KOs seem to be more common than Star KOs and Screen KOs. In Versus Mode, upper Blast KOs occur 50% of the time, Star KOs occur 30% of the time, and Screen KOs occur 20% of the time. In Training Mode, Screen KOs are disabled (from patch 1.0.8 of "Smash 4"), making upper Blast KOs occur 70% of the time, which is 20% more common than Star KOs. In certain stages that disable Star KOs due to either format or background, upper Blast KOs occur 80% of the time, which is 30% more common than Screen KOs. In certain modes and certain stages that disable both Star KOs and Screen KOs due to format and background, upper Blast KOs occur 100% of the time. Vertical knockback cap is a factor (from "Smash 4"), as being launched vertically at an extreme speed can only result in an upper Blast KO, especially with the balloon knockback in play; however, even at a very high knockback speed, Star KOs and Screen KOs can still occur. During the last five seconds of the match and Sudden Death, Star KOs and Screen KOs are disabled. In addition to that, on the player's last stock in "Ultimate", Star KOs and Screen KOs are toned down in favor of Finish Zoom/Final Zoom (high knockback from a move for a likely game-winning KO, unless the knockback from that move is low enough to avoid triggering that feature). In the first three "Smash" games, Star KOs are much more common; Star KOs occur 90% of the time, and Screen KOs occur 10% of the time.
It's one thing to add upper Blast KOs to the mix for competitive players. But to have no option to turn Star KOs/Screen KOs on or off for most stages (and Training Mode, as Screen KOs never occur) in "Ultimate" is very disappointing. Leading up to "Smash 4", Sakurai did mention how they were lessening the RNG factor of Star KOs. But all they did was stop Star KOs and Screen KOs from occurring during the last five seconds of the match and Sudden Death, and that's not enough to fix the whole problem. Unfair losses (as well as opponents being unable to prevent certain characters from charging up, and getting 1v2'd or the other team healing during a Star KO or a Screen KO) can still occur, whether the match is timed or not. Even the vertical knockback cap being a factor to stop Star KOs and Screen KOs at from occurring at extreme speeds doesn't fix the whole problem. And although Star KOs and Screen KOs are toned down in favor of Finish Zoom/Final Zoom in "Ultimate", it certainly won't be the last time a player gets screwed over on the last stock.
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So, yeah, that's pretty much how the upper blast line is in "Ultimate". It may change in a patch update, depending on how the developers notice the competitive outcome of matches.
The bad news is, players can still get screwed over by Star KOs and Screen KOs on the last stock, even when toned down in favor of the Finish Zoom/Final Zoom.
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Now, on why this is more bad news for me personally... I want to do the 999% match/goal on 6 specific characters I have in mind, and part of my goal is to end it with an INTENTIONAL Star KO after that specific character tortures that character on the last stock, as well as taunting afterwards. Screen KO ending is acceptable. Upper Blast KO ending, however, is completely unacceptable, and would definitely be an automatic restart. Since Star KOs are disabled in favor of Finish Zoom/Final Zoom, that means I have to make sure the cute character (Yoshi, Diddy Kong, Pikachu, Kirby, Jigglypuff, and Pichu on my 'cuties' list) does an up smash (forward smash from Diddy Kong; horizontal and vertical knockback from it) at a relatively low percentage (mostly between 90% to 100%), and that's with Rage being in play (from 35% to 150%). Relatively weak ending, compared to the one I wanted for "Smash 64" and someday "Melee", but that's the best I can come up with. Even with that, the chances of my 999% match/goal being successful is 30% or 50% at best (10% or 20% at best with the Finish Zoom/Final Zoom triggered). And I can't really rely on Screen KOs because they're rarer than Star KOs. That's a pretty big problem for me, as it'll be way more frustrating than it needs to be.
![Frown :( :(](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
The amount of attempts is probably going to hit the hundreds digit for "Ultimate", compared to hitting the tens digit for "Smash 64" and "Melee". So...may the game have mercy on me and the other player helping out in the future. *sigh*
By the way, since I played as Mario in "Smash 64" for the 999% match/goal, I have to stick to that character all the way to the end. So, yeah...with Mario's moveset being changed since "Smash 64" and especially after "Melee"... *sarcastically* I'm sure that's going to be fun.
Please don't be mean, everyone. And please don't be disrespectful to me and my goal. I've had bad experiences with that in the past, and I certainly don't want that here now.
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I still prefer Star KOs/Screen KOs to this day, but I do see why they are often an issue in competitive play. It's truly a shame that they're not iconic anymore, as of "Smash 4" and especially "Ultimate". I just wish there was a toggle or frequency on them.
RIP Star KOs/Screen KOs (1999-2001, 2008). You will be sorely missed.
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Oh, and about "Project Ultimate", even if that mod is finished, it may never get publicly released, mostly because of Nintendo. It's really a shame.