Firstly, the remake looks intriguing, while I will wait a bit before trying, as someone who is both a software engineer and who has spent many years picking up and reworking/rewriting other people's work, I have a quick suggestion or two;
Planned and yep, I'm keeping that format. Please read my developer's notes for that what I intend to keep. I'll be trying my best to retain the essence of AIF as much and as true possibly I could it could be within a VN format.
You mention that you want to be faithful to the original but also add additional "side content". I strongly suggest that you finish your remake of the original story first, but that everytime you feel that a side path could open up you make a note to come back to it.
This will benefit you in a couple of ways;
1 - You will have a very thorough understanding of all of the options that the original game offered, and so will be able to remove any 'side story' ideas that you had, which end up conflicting with the original game.
2 - By finishing your redo of the main game first, your mindset and writing style will be as practiced as they can be to copy and maintain the 'Cadance on language' or 'emulation of the writing tone' (I don't know the English word for this). This will mean that any 'side story' content you make will fit more smoothly with the main game and not be jarring to the players.
3 - After having completed the 'whole original game' you will have a better idea of what type of additional content your (hopefully larger) following of players and $upporters is wanting.
I don't really care to get into a pro/con about different fetishes that you could or should add content for (not the point of this post). Suffice it to say that by the time you have 'remade' the main game (assuming you don't 'fuck it up'
), you might (hopefully) be in the situation of having a large group of supporters. In this situation, they will likely be wanting more content (as naturally happens).
It will be these people (the $upporters who have stuck with you for the whole process) that are likely to stick around even longer as you add more 'similar in writing/style' content to flush out the main game. Asking your supporters at that time what type of content (fetishes etc.) you could add will be much better than "asking the masses" while still trying to work on the main game.
It will also mean less shitstorms for adding unwanted content, as your $upport base is already defined.
SantiPe Hi, about the harem tag, well, if 3 girls count as a harem then sure I can include that. The original had an ending with 3 girls. I mean, sure you get to screw around all the chicks but don't really end up having sort of a harem - if that counts/accounts for having a harem tag, let me know.
Defintion of a Harem relationship is "three or more LI's sharing the MC with each other"
Definition of a Polyamorus relationship is "Multiple LI's who are all in a (loving) relationship with each other.
The main difference here is that a Poly relationship has the LI's in love with each other (usually sexually, without the MC being involved).
While a harem has the MC as the primary focus of the relationship, with the LI's being sexual with the MC only (except for threesomes/moresomes that have the MC's direct involvement).
A harem with only two LI's is typically called a 'Thrupple'
Not sure what is in the original game, but hopefully this will help you define/tag accordingly.
Would also recommend that you observe the "one instance is enough to tag the game" rule. One instance is enough that the game should be tagged for it as transparency is always key.
Hope the info is constructive and helps.
Genuinely wish you the best with this project.