Re: Your translation preference?
First of all, changing the perspective of a text means more than just interchanging "[Name]" with "I" or "her" with "my". To take your example: "I desperately twist my body trying to free myself from the restraints, but despite that the meat flower continues to tear off my clothes." just seems somewhat wrong to me. A character being restrained would not normally describe the situation in such a dry way. As for an inner monologue, you'd expect something like "Ugh, I can't break free... What?! That thing is tearing of my clothes!" or if the character were to adress the meat flower, you'd expect to hear something like "Let go of me! Hey! Don't rip my clothes!". Hence it's not just a question about whether using 1st person or 3rd person perspective, but it's about entirely rewriting the sentence.
It should be mentioned, however, that this whole "manipulative translation" thing does exist. There are people who'd actually change a text according to their ideology (or rather preference, in the case of H-Games) and merely see the source text as an inspiration rather than an actual source text. But in the end, that's just rewriting, not translating. It also causes a considerable amount of extra work. Not to mention that most people (that I'm aware of) who'd be willing to use such a strategy, tend to be bad translators. That is, they also incorporate errors in their translations that have nothing to do do with the style itself. Go figure.
Then again, from a player's perspective, while most people tend to say "keep the original the way it is", most of most people will never compare the translation to the original... Obviously, as they wouldn't normally need a translation if they could read the original. And as long as there are no blatant errors, many people may not even notice any changes done in the translation. Sometimes changes can even enhance a translation when compared to the original.
Furthermore, as a rogue translator, you are not bound by the will of the game creator or even those reading your translation (unless you are paid for your translation or such, but that's another topic). So just doing what you deem appropriate may also work. If you don't have fun translating, you may as well don't. In the worst case, nobody likes your translation. More likely, however, at least some people will be pleased.
Having said all that, there most often are good reasons why a game creator chooses a certain writing style over another. I remember some of the vore scenes in Card Quest 2... which basically had a dialogue style, though the protagonist's share of speech was reduced mainly to "Ugh"s, "Ah"s and "No"s. Both a 1st person and 3rd person perspective would have been entirely inappropriate. The 1st person perspective because the protagonist, while being eaten alive or being inside the enemy's stomach, would not really seem helpless if she could coherently think or even talk back to the opponent, the 3rd person perspective (always sounding descriptory and somewhat objective) because it would not really demonstrate the dominance relation between the protagonist and the opponent.
So, in short, unless there are really good reasons to make changes to the original (which do in fact exist but should not be arbitrary), you are better off staying loyal to the original. Outright changing the perspective seems to be too far off by any measure that I can think of right now. If you are willing to translate a game but prefer a 1st person perspective, then it may be better to just look for a game that features such a style to begin with.