The disadvantages with regards to the proposed research changes outweigh their advantages. Both advantages and disadvantages will be discussed below.
The main advantages occur in early-game, in which more units are accessible sooner, hence game pacing will increase and a much wider variety of strategies will be available. No longer are games restricted to infantry stacks in the first few days. The research costs in the beginning are manageable for the early game economy, which is characterized by a surplus of food. However, given the time costs of each upgrade are so short, the player would soon run out of rare materials, and now it is no longer possible to be constantly researching. A typical production for rare materials in early game is around +100/hr. The potentially accessible researches, for example in the naval tab are have huge opportunity costs given their cost in rare materials. The current costs would be problematic in games where diversification is needed, ie. Pacific Conquest or World at War.
The main disadvantage is that the costs for the researches during middle game are too high. Given that it costs more rare materials and food for research, it now sacrifices the option of building industrial complexes on resource tiles for economic development. In particular, food and rare material would be a much more valuable resource. Moreover, during this stage of the game, there are many wars ongoing, and those who have conquered lands should start to realize that their food productions are decreasing due to the food consumption of the population and upkeep from the armies. The flexibility of early-game is now reduced as more typically used units dominate many others. For example, the tactical bomber, a focused research on this would result in highly valuable returns compared to a focused research in troops with low anti-air defense values. The costs for focusing solely on the tactical bombers are comparable to troops that it easily defeats. Hence, it will become disadvantageous to research a larger variety of units, and focusing on units such as artillery, and tactical bombers will be norm for more experienced players. In effect, the amount of strategies to work with will be decreased due to the economic costs of researching them. Although the accessibility of researches is earlier, the feasibility of having a particular research is far lower. This would lead to fewer researches being accessible to players, and thus more limited strategies at play on the battlefield. The new research system effectively forces the player to focus on just one or two research streams. Even though some researches are cheap, the resources invested into those can be better used on specialization. ie. Researching many different tanks, only to be defeated by tactical bombers.
Feel free to provide counter-arguments and feedback.
Not a bad thing in our eyes. Fast buildup time means faster destruction. Makes decisions on where and when to place buildings more meaningful.