I want to add my (extremely long-winded) two cents into the thread. I understand that there are conflicting interests that must be balanced and that both sides have some very good points. From the side of hint2, you have to understand that he (she?) has invested a great deal of time and effort into this game assuming that the diamonds have a certain value in relation to time/effort. In other words, assuming a diamond value fixed in term of time spent in game, does the pricing of the GB represent a shift (lower) from the previous diamond cost value of existing game features.
To do this requires one to quantify the effects of various Great Buildings relative to the cost in both space requirements and time value which is a difficult effort due to multiple dependencies that do not give a single answer. Based on surface evaluations, it appears that the very active player currently at a very advanced stage will be in the best position to leverage a moderate diamond investment to separate themselves from the very active advanced non-diamond player. In other words, the introduction of this feature appears to have caused a large devaluation in the PREVIOUSLY INVESTED time value of the highly active non-diamond player.
A secondary effect is the risk that this subset of players that has been most negatively impacted will abandon the game leaving an even greater gap between the player tiers. It also doesn't help that the tier of players below the top tiers that would be willing to spend diamonds (I put myself in that category) would benefit much from investing diamonds to acquire BP as the space investment and the relatively few buildings that can be modified provide less of a return to me than they do for a top tier player.
It seems to me that the implementation of the GB has been less than optimal in creating a greater imbalance favoring top tier players that are also diamond users. While this might be more understandable if the level of diamond investment were such to create a great inflow of dollars to Innogames that creates a greater bond between all customer subsets spending diamonds resulting in greater diamond purchases down the road (remember that for online gaming companies, a transaction that converts a free customer to a paying customer has a value well beyond the dollar value of that transaction and transactions from already paying customers). My concern is that the inability of lower tier players to leverage their diamond investment in acquiring BP's into game advancement at the rate that they initially hoped could lead to an effect that is less than the desired level. I acknowledge that I could be overstating this risk if the coolness factor of having a GB for players outside the top tier outweighs the actual building effects in terms of game progression. Also, the relative cheapness in diamond terms could mean that the buildings are delivering a greater in game effect than other diamond spending alternatives for players outside of the top tier.
Getting back to the main point, there are some very delicate interests that need to be balanced - hard core not-paying players that contribute to the game experience, converting non-paying customers into paying customers without alienating the non-paying contributing base, increasing the rate and level from current diamond buyers without incurring a backlash, game balancing (immediate effects, intermediate and long-term), realism as well as others I may have omitted. It certainly is not a simple task and one that is guaranteed to result in expressions of dissatisfaction from every corner.
With that being said, I think that an emphasis on minimizing the game balance effects among the top tier players segmented into diamond players and non-diamond players should have been made a higher priority in the initial implementation. I suppose that Innogames is relying on the top tier non-diamond players to remain loyal while they endure the greatest negative impact (as these players relate their progress against top tier diamonders). If that is what ultimately happens, I suppose that the gamble may pay off, at least in the short run. My fear is that the top tier diamond players leverage the low diamond cost of the GB to create a gap at the tap so large that the only way to address it is through a measure that will then be seen as unfair by the top tier diamonders. Since this segment of highly active paying customers is the most desirable segment from a business standpoint, it would be a difficult business decision to implement measures that specifically target them even if they have received the greatest benefit from the initial implementation. It would require a perspective of enlightened self-interest to accept the changes without resistance for the best interests of FOE for them to accept without great resistance.
This is why I think that the argument that imbalances can be addressed later fall short of the mark, IMO. I think that it is critical that you get it right on the first go even if there is a resulting delay. Introducing imbalance into the game has an amplified negative effect even if it is corrected later. For one, there is no way to address the imbalance that applies fairly to all entrants because they will have had varying positive and negative effects from the imbalance that was previously introduced. Fair compensation would require that compensating penalties and benefits by applied that are (at least somewhat) in proportion to the benefits and penalties that resulted from the imbalance being addressed.
From a game balance optimization perspective, the effects of diamonds would be limited primarily to overcoming an activity gap which would produce diminishing effects for the highly active player (at least when that player is also in the top tier of points). Essentially, there would be a logarithmic relation between diamonds and game progression. However, it may be that this conflicts with financial considerations and thus not viable to implement. In terms of how this would apply to BP acquisition, a sliding scale for diamond price of BP depending on the players current level, a diminished effect of GB based on how the BP's were acquired, a lower cap level for purchased rather than organically produced GB's.
Ultimately, it would probably be a "fairer" game if Innogames were to switch to a pure subscription model with the ability to Grandfather in some of the existing long-time players with free subscriptions ranging from three months to one or two years. Maybe you could throw in diamond effects that only served to enhance your activity (e.g. auto-collect from buildings when you are away from your computer).
