i'm right there with you majere.
i put up with a lot of stuff that i think is messed up in order to read yuri. i try to take what i can from a work, but i definitely don't agree that the rest of an author's work should be irrelevant. the reason i went looking at the pixiv was because things in this comic were making me uncomfortable, so i looked to the author's other stuff to see if maybe my discomfort was just a one off thing.
i found their other comics and illustrations even more creepy, and it definitely shows that this isn't an aberration. this element of young looking women is a major focus of their work, and that puts this work into a different context.
i'm not telling anyone that they shouldn't read hino-san no baka because of this. all i am saying is that there is a place for discussion about the author's intent. i can overlook a few dodgy things here and there, but when the content you like is the aberration, and the rest of their stuff is problematic, i think it warrants a discussion.
the same way you would put any art into perspective, both historical and personal.
is it creepy that this comic keeps bringing up how young koguma looks? well, for me, when i see the rest of this author's work, yes. it is creepy.