This was a problem ever since the I/O car classes started shifting away from the original car classes, this happened many years ago and persists to this day, no surprise.
Modifying RVGL in order to make it compatible with the fickle and subjective I/O classes would be an affront to the game: RVGL and Re-Volt. One day you want this, another you will want to change something or redefine something else. There is also no need to add another layer of complexity to something so simple as 5 car classes (maybe Super Pro could be added to distinguish it from actual Pros… they would not mix themselves up in Pro single-player races with regular Pros, while being not a major modification to the game, but I'm not sure about it either)
Modifying the stock car classes is not an option, it's modifying core assets (stock cars, tracks etc.) to someone's will.
It's true that some cars are not balanced (for example: AMW vs the other 4 Pros, Toyeca being too good overall, Pest Control and Pole Poz vs Adeon and Zipper, some other examples on lower classes as well…), but to be honest it was always this way. I would prefer if the cars were "kinda" balanced, where all stock cars from a specific class could compete with each other on the same track while being different from each other thus having advantage on different types or parts of tracks, but that how life is and we have to cope with it. The best way to cope with it is to stick to the stock car classes and treat cars in these classes as benchmarks: the weakest and the strongest cars in a specific class would be a benchmark for custom cars: customs in a specific class should never be weaker (but can be as weak or similarly weak) than the weakest car in the class, for fast cars in their classes they should be also comparably strong (not stronger or too strong) to the best car in their dedicated class.
But the above isn't the case, as the dedicated car class for custom cars sometimes does not match it's competitive strength, usually the car being too strong for it's dedicated class (for example Advanced being OP in Advanced class, but average in Semi-Pro races).
Years ago I offered a radical solution for that, which would fix both the problem of the I/O car classes bringing confusion for players and it would not require modifying an entire game to address one community's will. Of course it was torpedoed and I lost any interest in I/O car packs since then. One (maybe serious) problem it brings back is that some cars will be strongly preferable to others in certain class races, degrading diversity in races. But players can always pick worse cars for an extra challenge, it's up to them… If they pick the best car, complaining about it being picked too often is kinda hypocritical. [And also the cool "Prugs" name would come out of use. Maybe rename Advanced to Prug?
Rather definitely don't think so.]
My (old and current) suggested solution is to:
1. Strictly stick to the in-game class ratings: Pro is Pro, so AMW can't be used in Semi-Pro races, Pole Poz and Pest Control can't be used in Advanced races etc. Of course you can do the reverse and use for example a Semi-Pro in Pro races, but it's up to hosts whether it's allowed and how big can the class difference be, whether an Advanced or Amateur or Rookie could be used in Pro etc.
2. Completely redo the I/O car pack, so that it would contain 5 (6 with Super Pro) car classes that would perfectly match it's stock class counterparts, both in name (not as important, but having different name for a car class list that contains cars that match stock classes would be pointless) and in competitiveness (very important). This would require removing cars from the track pack that are classified to a different class in the pack class list compared to the assigned cars' parameters class. This would also require removing cars from the pack that are too strong or too weak compared to the rest of stock+custom cars within their class. Many cars would face removal, but why authors made them uncompetitive (too strong or too weak) in their class? It's up to them to update the cars or leave them be, having the car outside of the pack.
In summary, very similar to Turbo's first post in the topic.
Just an opinion of an I/O expat, it's not like any changes to I/O packs influences me or my cars/tracks folders, just sharing an opinion on a topic which consequences do not affect me…
Off Topic
While writing this comment it came to my mind that actually "car classes" [actually called "Rating | Skill level (rookie, amateur, ...)" in parameters.txt and in-game] in their names do not refer to the cars themselves (their competitiveness, speed etc), but rather the skill that player is supposed to have while progressing in the game, the better he is the better cars he can drive and are dedicated for the player to use. Like: car can be a "Slug", but the player/user of the car is a "Rookie", as he just started playing. When he progresses, he gets better, he is an Amateur, an Advanced player, a Semi-professional and a Professional player, but a car can be a "Pro" or a "Prug" car. Or/and this refers to the skill required to use a specific car, as slower cars are easier to control and drive, at least in general. But treating car "Rating" as something that divides cars into separate speed/competitiveness groups (classes) is obviously the way to go and should be treated accordingly, as it is.
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