You\'re doing a great and very important work here, guys! I beleive that your researches should become some sort of canonical thing in nearest future. But maybe it\'s too early to mess with costs of parts? We have some behavioral & unmeasurable characteristics, like \'overall coolness\', \'design\' and \'non-red-texture\' for example. Also, it somewhat hard for me to include simultaneously \'drag\', \'tolerance\', \'heat proof or-whatever-it-named\' and all listed above fuel-capacities et cetera in one big formula/equation. I mean, it\'s great to have coefficient of vanility, and model balanced parts depending on it, but don\'t you think that computing cost depending on it is too complicated and, er, not needed at all? Good point! To split equations it\'s a good way to achieve flexibility and still have objective values, which measures how much part is well-balanced. I find it hard to express my thoughts in english without knowledge both in equations and language at all. Sincerely, your poorly-speaking russian comrade.