re friendship with ded enforcer - idk I never really expected much of him outside of 'plot driver', though now that you mention it I /am/ curious as to why that should be such a huge driving force
idk I actually don't really like kogami and idg why they're considered ~two sides of the same coin~ etc - true they both strategize similarly, but then again so does/ can akane, in badass mode, it's what 'smart' is in the show soooo idk why it is anything unique
aside from that, their main motivations are just quite unrelated? makishima wants to psychologically toy w people in joker-style while kogami is out for you-killed-my-friend revenge, I can't really see any underlying thematic way they are foils to each other
if anything makishima is obviously superior/ the winner, he successfully 'played' kogami into becoming who he wanted him to be / irreversibly breaking from the system, and if anything it's akane/kogami who are foils for each other, re their ideas of justice
re the circle ending - haha, just about all of the ending were circle allusions! kogami becoming the next makishima, isolated and an outcast from society, rejecting society / 'moving past it' kinda sorta like makishima did (oh, really loved the shot of him reading Swann's Way in the epilogue -- earlier in the series makishima eats a madeline with tea, which comes up in the book)
and ginoza losing his arm and becoming an enforcer like his dad - haha, gino was such a surprise awesome for me, def did not expect to enjoy his storyline as much as i did! it was about 200% predictable and cheesy, but his scenes in the last (two?) eps were just heartwrenching (probably lots of pixiv fanart had a say in that as well)
(i also really liked choe fsr! maybe im reading too much into it but i thought that vaguely throwaway line, where he said to makishima that watching him makes him (choe) think that he's been missing out on something his whole life, was reaaaally intriuging - wonder what that 'something' is, etc)
anyway but about what you said about the ending, idk what i took away from that was more that it wasn't an exact circle of the first? I don't have the raw eps (tempted to get some just to compare screenshots though now that you mention it) - such as, while gino told akane enforcers were dogs not humans, akane treats them with much more respect
point I thought they were trying to make is that akane's philosophy is the only one that can enact real change? as in, true it's slow, and true, it's not easy and it won't bring you insta-satisfaction (of the three, makishima found freedom and understanding, kogami got his personal vengeance, she's the only one who hasn't 100% accomplished her goal by series' end) but she's the only one who stands any real chance of being able to change the system and do any real good?
that whole thing kinda reminded me of something I randomly read/ came across before, that the zeitgeist/ society's viewpoint on big things like racial and gender equality etc, come about not so much because bloody revolution and anarchy change the minds of the people in power, but more of because the new generation is brought up with differing views, and when they come to power things are changed
to me that's what I liked about the ending, actually? I found it more convincing from akane than it would've coming from kogami, more realistic as well
kogami didn't want to enact real ~societal change, he was really just after petty vengeance (and unexplained at that!)
(lol i don't really like kogami much overall, he really is just not as interesting/ explained/ depth-y as makishima (or even akane) so attempts to put him on the same level as makishima i just really find quite askjldfhlkjdf)
while my sentiments are not so much "writers ran out of episodes", ia with you though that i do feel pretty unfulfilled about the ending & i would like to see some more about how exactly the system is changed, that was p much the only other thing i disliked about the anime (& that the music was not as standout as madoka imo)