I'm more or less in the same boat as you i've watched the same seasons and that is it, i've learned more about the SAO lore reading this thread, yeah the hardore fans didn't like that and also the not so serious according to Fujino "Asuna's memory manipulation" in order to insert Inoda in SAO past events before FOG, in my opinion they were just suggestions to nudge her into further corruption, but the fans saw as hypnosis/mindbreak which are lame/lazy trope for NTR and people don't like much.
The Sugu case was because in one of the Fujino's Q&A someone ask him if Inoda would NTR Kirito's sister, and he said point blank NO but never said anything about Sex which are 2 very different things, and if you are playing the game you can notice how Fujino let the character floating arround after he sacked Hebishima from the story until he came up with the Stalker Yandere/Brocon Rapist Spy plot for her and many fans started to build theories and plots upon that, but with one thing in common she would never be touched by Inoda i any way shape or form.
Last update Fujino kind of changed that a litlle with her now being target by Inoda, and with that the fan base went bananas some liking the idea others hating.
About the endings, Fujino is being vague on purpose (spoilers), but he did mention multiple endings, Asuna and kirito's Stats will be important somehow, the players choices also will have a role and maybe he will do a epilogue or epilogues.
By the epilogue alone i think will not have a early ending, and that will be more to Fujino save face if the endings were lacking which they probably will be.