It's not your fault that the game has entire subscriptions of issues, you did the best you could with what the Dev made... which just wasn't great. In terms of bugs... or things that might be bugs anyway... I've noticed the following:
-Lena's affection score keeps resetting over and over so it's actually impossible to reach 100 without cheating, and it won't stay at 100 even if you do cheat. I'm not sure if it's possible to unlock the Ranch job with how that works.
-If you try to open the weapon/armor upgrade menu for Eleanor prior to fighting the first boss after she shows up, you get an undefined error and you have to restart the game.
-If you access the Green Grocer early enough, you can buy the grape things for free for some reason.
-The Sex Shop scene when you go to Sex Shop at night didn't display the image, just had a black screen with the text box... didn't try it again or in the gallery to see if it's a consistent behavior.
-Sometimes, items appear in the inventory with a count of x0 and refuse to take up new items. I genuinely have no idea what triggers this, but it's especially annoying for Power Stones and can make grinding them even more annoying than it already is. I
think it's related to gifting them... but I've seen this trigger with basic healing potions too even when I didn't use any of them...
-Upgrading Amy's weapon and/or armor to the max fucks up her mana bar. It dropped to 45-ish, and even using the stats cheat you put in the game only raises it to ~1000-something instead of 9999.
-In general, I think there's something screwy with the higher level weapons/armor. Pretty sure Eleanor is supposed to get a 4% HP regen bonus total, but even with 9999 HP, she only regenerated 45 HP per turn, instead of 396 per turn. Similar issue for witch-butt's Mana-regen. Not entirely sure about other stats. Not sure if evasion even works... etc.
-One part time job said that you earned 100k Money, when it actually gives 10k. I think it was the Nursery job? I don't remember for sure.
...aaaand that's it off the top of my head.
On a semi-related note, I edited a save at one point to give myself 100 Power Stones to reach 100 Lena affection in one go (which works even though the game doesn't let you reach 100 count on any item if you collect/buy them naturally...) and I noticed that there's a ton of items in there that don't seem to have been used for anything in the actual game? It honestly feels like the Dev had much bigger plans for this and just gave up on them for some reason.
As for the endings...
Moving on. For the Interracial thing, I was mostly curious. I don't like it or dislike it, and I'm definitely not invested enough in this particular game to kick a fuss about it in any way.
As I said at the start though, there's no need to be sorry about anything. You did as good of a job with the translation as you could, imho, it's not your fault that the game has a lot of problems. You're a fan-translator, not a professional QA team that gets paid to fix shit... and even that wouldn't have fixed the poor writing of the story and weird ass pacing.
Like how Lena kind of just disappears after the Yakuza thing is over aside from the part-time job thing and nothing really gets addressed about her. Among many other issues that pop up narratively....
Furthermore, I notice these things more than most people would on account of my own tangents in writing/world-building and other things.