When you have over 1700+ vehicles in game, you cannot have manually adjusted numbers for every vehicle. That is simply impossible and unreasonable to expect.
With that said, we have been working on some changes specifically for event vehicles repair costs, that we hope to be able to share very soon.
Of course not
Data is a statistical fact. Feedback and personal opinion is subject to personal bias, certain perspective and confirmation bias that cannot be used as the sole point of cost calculation.
We use data and the actual factual numbers to determine the values with all feedback taken into account, but there are very clear and obvious reasons why you cannot use personal opinion or only manual adjustment in our game with 1700+ machines.