Your dog hunts...if Sviatslov signs and the long guards can guard short guards. It hunts intermittently if the long guards find a lot of situations where they cannot guard the short guards.
Short guards are going to become more prevalent, rather than less, with the rules changes favoring the offensive perimeter player. There just are a lot more short guards to sign and play at any given time, so if their shortness is made less of a disadvantage by rules changes, more play.
In the age of the trey, with tight calls favoring offense, pretty much anyone of any height can offend on the perimeter, if he has a 40% trey, ambidexterity on the dribble, and a quick first step. With those three things, he can penetrate for a two and a FT virtually every play, when not drilling the trey; this was the Wisconsin Lesson of last season. After burners, like Mason's, are optional now. The three's the thing. It creates the space necessary for even a average driver to get a shoulder by his man and go and exploit the favorable whistle for the offense. Conner, if he can get his trey sighted to 40% has as much athleticism as any of the Wisconsin lead guards last season including their point guard, who was actually NOT at all a Tyshawn Taylor on the drive, just slightly above average on in the X-axis speed department.
In the age of the trey, with tight calls favoring offense, offense reduces to finding a point guard and two wings that can each shoot 40% plus from deep. Teams that can field three such players with a rim protector and rebounding power forward are the gold standard.
Imagine last year's Wisconsin perimeter with a 5-star four last season. It would have been an undefeated ring season for Wisconsin. Even with stiffs for 4s, they made it to the Semifinals.
So: how does this relate to your post and Self's desire to sign Sviatslov?
At the very least, Self, the savant of matching up, wants to be able to field a perimeter of 3 40% trifectates to match up with teams that do that.
More likely, though, Self just gets that the rules changes are here to stay for a few years and three, 3PT perimeter shooters are king until the rules change again.
In turn, this means that Frank Mason's PT, magnificent speed demon though he is, is likely to come from spelling Frankamp the Trifectate PG in situations where going long at point to keep three trey ballers on the perimeter is not feasible due to defensive vulnerability.
Signing Sviatslov means Self can keep three trey ballers on the perimeter for as long as he likes. Selden (assuming his knee heals and permits him to ascend to 40%--a reasonable possibility), Greene (assuming he gets under control), CF (assuming he can get his shot off for 40% accuracy), and Sviatslov (assuming he is strong and quick footed enough to guard and offend in D1), are four credible trey ball threats. Four means Self can, if defensive abilities permit, basically keep three trey ballers on the perimeter all game long, which is the new killer app of the game.
(Note: well, it is not really new, is it? Lute Olsen's Arizona ring team with Bibby, Miles Simon, and I forget the third trey dinger proved that it worked like a charm back in helmet hair's day.)
And with Mason, Self has the flexibility to matchup short at any guard position, when needed; that is Mason's real, and not insignificant function on next year's team. As a result, while I agree with you on your rotation, and assessment that Mason may be farther down the PT food chain this season, I don't see much likelihood of him redshirting, unless he just can't cut it academically, in which case he would almost certainly not be redshirted and transfer end of season.
Of course there is one possibility that neither of us has considered so far. Frank, arguably a very hungry guy from the streets with more than a little moxie and drive to to get as far as he has, could read the writing on the wall, and start shooting 400 treys a day between now and October 15, and wind up with a 40% trey gun himself. Mario Chalmers made himself into a 40% guy once upon a time. It can be done, though it is rare.
Imagine this team with Frank as a credible trey threat on the perimeter. It could keep three 40% trifectates on the perimeter 40mpg, AND matchup short or long.
Hmmmmm, now that's a thought to savor.
There is one more wild card in all of this and his first name is Devonte. I fall into the camp that suspects he probably is NOT going to be an impact player, despite expressed Selfian enthusiasms. I suspect this because of recruiting rank, because of Appalachian State, because of thinness, because of an all right-handed highlight feed, and because of the seemingly implied swap that occurred to free the team from Tharpe and so perhaps Tharpe and Self from having to live with the selfie and Tharpe's limitations. To shed Tharpe, and still stay in the preferred recruiting line at the Brewster basketball factory, er, academy, it at least appears that Self might have taken Devonte, even if Devonte were a sight-challenged, little person with two left foot prosthetics. I cannot forget just how enthusiastic Self was about Royce Woolridge, Naadir Tharpe, and so discount somewhat his remarks about how much better KU got by signing him. I also cannot forget how more highly ranked players like Tyrell Reed and Conner Frankamp and EJ and Travis Releford could not really contribute much their freshman seasons, not just because of players ahead of them, but because of real limitations in their stages of development. I would even go so far as to say it is unlikely Devonte will be an impact player next season.
But there are the occasional Kevin Young and Frank Mason types that are hungry, gritty types beyond intimidation, either by Self, or opposing teams, that Self occasionally finds rotation minutes for just because of their toughness and a shortage of returning tough, gritty talent.
If Devonte were a particularly tough customer, and if he were able to pot the triceratop at 38-40%, and if he could guard and protect, well, then heck yes, he could get in the rotation, because god always favors another ball handler at the point. But those are one heckuva lot of ifs. And it wouldn't take much improvement by Conner and Frank to make Devonte an obvious choice for throwing a rouge Italian smoking jacket, especially with the crowding created by Sviatslov possibly signing.
Ah, the off season. It is a time when all hopes and all doubts are possible, and the harsh realities of "who can get her done" awaits in a misty future full of unforeseeable outcomes.