eFFecT, some guys from the TrackMania One developers and me have got some suggestions for the upcoming ManiaPlanet update(s). Since ManiaPlanet 4 we've got tons of tools to customize work for all kind of idead. The best example are vehicle items. Since we got this great feature, we can have cars, which are similar to TMUF ones. Since we got 3 parameters, we can't change too much, but it's still great.
So as a lot people from the community are also complaining about hitboxes, cameras and more possibilities for custom phsyics, we've got 3 suggestions we would love to see in the future.
Resizable Hitboxes
It would be a great feature to have the possibility of a custom hitbox size. Not for normal skins or models, as ofc there the envi hitbox must be used. But it would be cool for titlepacks, which have an own ranking (and there it wouldn't affect leaderboards, if you could take cuts with a e.g. smaller car)
I would have 2 ideas to realize that:
1. Hitbox object in the dae/fbx file
You would have a file called 'Hitbox' in the file before the import, which would set the maximal hit bounds
Example:

2. Option to rescale the existing hitbox of the base car
You would have a new parameter in the vehicle item editor, which sets the rescale factor for the hitbox of the Archtype. But in the end, the car will have the same size and won't be rescaled
Example:

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So expecially this feature would be very important for TrackMania One Alpine, so the car could be 1X smaller and the blocks are as big as in TMUF again (now they are only 50% of the original size)
Custom Camera Angle
For custom vehicles it could be very useful to have another(other) parameter(s) to change the camera position for the item. As Valley- and Lagoon-Car are not very high and the camera isn't that high, it is annoying, if the car model is higher than the hitbox and blocks the whole field of view. Again, I would have two ideas to solve this:
1. Set the camera position in the model as empty
So in 3D-Software you can create emptys, which are just indicators for things made by script. It would be the same as spawns in Items. The idea is to have an object or empty, which is called 'Camera' or so and which sets the static position of the later camera ingame.
Example:

2. Having 3 parameters to set the position/coordinates or the offset
The other way would be to have 3 parameters in the vehicle item editor, which a. set the coordinates of the camera or b. set the offset from the current camera in all axis.
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This feature would be extremely useful to TM2UF or TMOne, because you would see more even with a big model.
More Physic-Values
At the end, having more freedom for custom phsyics would be cool as well. Currently we have got Acceleration, Control and Gravity. But it would be also useful to be able to say when/if,
1. the car starts to break out/drift (DriftCoef)
2. the car behaves like Desert in curves (WheelCoef)
3. the car behaves while in air time (I mean, if the front or back are falling down earlier) (WeigthCoef)
4. the car behaves on turbo, does it boost after turbo touch or does it still boost when even having contact with normal surfaces? Here maybe a parameter to set the 'after-turbo-boosting-time' would be good (TurboCoef)
5. the car does have an airbrake (AirbrakeCoef, Boolean)
6. the car reaches a maximum speed, like 500km/h (MaxSpeedCoef)
There are more for sure, but these are the most important additions to vehicles in my opinion.
That was pretty much, but I hope I will find much support by the community, and I also hope to get an answer or actual updates with it soon

Have a great day and thank you in advance,
Florenzius