I like seeing composition interpretations of every work of Gallery of Violence that people are starting to make in tags. And I wanna say beforehand that any of your insights are valid!!! AND I WANT TO SEE THEM, but also for anyone who's curious, I decided to make a post about some ideas I myself intended to show by those art pieces + my headcanons on every character-autor as an artist because i tried to give them each sorta their own style. JJK MANGA SPOILERS AHEAD!!!
Obviously pictures death paintings and Yuji aka his children, but the detail thing is death paintings (lol they actually are paintings now) are blurred by black paint since Kenjaku perceive's them as failed projects. Art headcanons are him using quite a lot of oil (not as much as Mahito tho) and yeah smudging projects he's disappointed in.
Suguru's portrait was done after his initial execution by Gojo, but Gojo ripped it apart after reveal of Kenjaku taking his body (idk where it would happened in canon, probably before fight with Sukuna). Toji's frame, glass and canvas are all torn apart with "bleeding" behind it are part of Satoru's art-headcanons - it's not about the fact he killed him by making him a badly centered donut, it's about his power manifest in such greatness that "not even a visual recreation can contain it". Yuji & Sukuna artwork isn't finished, since he never actually executed Yuji and Did not defeat Sukuna. He is using fancy frames for Suguru (gosh i love his name idk it just sounds yummy T-T) and Yuji cause he sees their death as a shameful loss for the world that needs to be mourned about. At the same time, Toji's and Sukuna's frames are simple since Gojo perceives them as obstacles only. Art headcanons are Satoru's determination to go past limitations such as frames and edges of canvas. He also probably gave Yuji's portrait some unbelievably long title. ALSO he uses only his name aka Satoru ć as his signature since I do not believe he gives a fuck about Gojo clan.
Stands right before Megumi's portrait, since when I made this Sukuna possessed his body, that's also the reason Megumi faced away from viewer - his personality was effectively suppressed at the time. Gojo has the biggest canvas since Sukuna enjoyed their fight and has some respect for him. I guess I should've made Jogo's piece, but i forgot about his fight...
Probably uses pastel and soft dry materials, maybe a little of tempera. Prefers smaller canvas for more control over process.
Addressing the elephant - empty frame represents his feeling of guilt for Shibuya incident deaths. We may not believe it's his fault, but he does, and that's why it's still there even if it's empty for us. Mahito's portrait has 3 kanji on this picture, but later when I made a poster out of his artwork i decided to simlpy name it ç . Yuji unlike Gojo sign his works as Itadori since he doesn't value himself and would probably pass his achievements to family name rather than his own. Works in mischtechnik and uses mainly color pencils, gouache, tempera and watercolors, maybe some acrylic. Often literally mixes them. He lacks basic academic knowledge so tries to follow all the "rules" of classical art but always gets carried away by his own feelings in the process.
Uses giant canvases a lot, not out of any respect for people on these canvases but because of his own immaturity and maximalism that comes with it, if he would win a fight with Yuji he'd give him a comically big one as a way to show off the win of his Ideals. He also made portraits of Nobara and Nanami so big exactly because their death (well I thought Nobara is dead at the time a painted this) was the way to shake Itadori's sanity. Uses the more oil and acrylic than anyone else, covering canvas in super thick layers of paint. Draws only with fingers (idk maybe with toes too, he's unhinged like that) and sometimes with painting knife.
ALSO I had headcanon for Toji drawing with coal some cool minimalistic artworks, but i didn't draw it. He probably would be pretty popular as an artist, but so bad at money management that any money he'd get were doomed to be wasted.