Hi ! Thanks for your feedback !
I see what you mean and I understand your frustration. Currently, the progression system is rather simple and indeed not based on past performances. Since performances are already based on the rating, if we reward good performances, a good player will inevitably become stronger the following year, perform better, and thus become even better, and so on. Conversely, a bad player will get worse. In my view, progression indicates the expected performance for the upcoming season rather than reflecting the results of the past season.
In your first example, if your player has a 73/73 rating (meaning no room for improvement), it indicates he’s over thirty and can only decline.
I understand this might be frustrating for young talents, but in reality, there are many young players who were dubbed 'the next Messi' or 'the next Zidane,' who were thought to have enormous potential but disappointed or whose progress was slowed (hence the significant drops in potential for some young players in the game). I did not want progression in the game to be linear. Nonetheless, even though potential can vary over time, a player with high potential is more likely, on average, to develop better than a player of the same level with average potential.
I'm not sure if this is very clear. I hope to introduce other features that might influence player development (like a coach or specific training), but I still want to maintain some randomness. I recently made slight adjustments to the overall progression to balance the game, which may change your experience.
Regarding the most important point, thank you for pointing it out! 'negotiation' is 'négociations' in French, and unfortunately, I am French… I'll correct that soon!