In dealing with company image, I think the maximum value attainable through marketing alone should be around the 50 mark. In order to go from 50 to 100, airlines should have to spend money on initiatives to improve the customer's experience. I have three off the top of my head used in the real world worth considering. I'm not sure how it would be implemented, but this would make it easier for smaller airlines to attain 100 ratings without breaking the bank since 100 CI airlines are usually the largest in a game world.Process Improvement/Six Sigma:
Customers don't feel averages--they feel variation. If you have a brand with wild variation in product delivery, your image won't be as high. Think of it as going to a fast food restaurant. If the average wait time is 2 minutes to get your food, but varies greatly where it takes 1 minute the first 9 times and 10 minutes the 10th time, you're not going to be too happy with the service as a whole. Undertaking a Process Improvement/Six Sigma initiative would involve training 1% of the workforce @ ~$10k/person and require the creation of a Process Improvement Department (with 0.1% of overall staff) with added salary expenses. The net benefit of doing this would be a maximum of +10 CI (+1 per year to a maximum of +10, by reducing variation in products/services offered) and a decrease in operating costs (by increasing efficiency/output of current employees) of 1% per year upto a maximum of 5% in years 5+. (1% in year 1, 2% in year 2, etc)Revenue Management:
This is big in hotel/airline/rental industries as an empty seat or hotel room is gone forever and is a lost opportunity. This is why you can goto a travel website and see different prices for tickets at different times. Using this would create a Revenue Management Department with added salary expense (~1 employee per aircraft). This would increase CI by making sure seats are always available for purchase. The ideal situation for airlines is to have exactly 1 empty seat on every flight. If there is more than 1 empty seat, you're charging too much. If there are 0 empty seats, you're not charging enough. Having a revenue management department would allow you to focus on 3 different strategies: maximize profit, maximize market share, or both (market share and profit are considered when pricing tickets). By either having cheaper tickets to sellout flights or making sure a seat is always available for purchase if so desired (even at a higher price--the only thing worse than an expensive ticket is not having any tickets available to buy), CI would increase +1/year to a maximum of +10 after 10 years. The net result will be happier customers (being able to buy cheap tickets or always having tickets available for purchase) and increased profits for airlines.Frequent Flyer Program:
We all know the bigger (and many smaller) carriers have frequent flyer/loyalty programs. Airlines could create a Frequent Flyer Program that costs 3% of revenues to maintain (which is the approximate return on airline credit cards) and would pay for the administration of the program as well as frequent flyer lounges/benefits at base airports and major destinations. This would be the most expensive program to implement and would snowball over time. The first year would provide a CI boost of +1, year 2 would be +3 (1+2), year 3 would be +6 (1+2+3), year 4 +10 (1+2+3+4), year 5 +15 (1+2+3+4+5), year 6 +20 (15+5), year 7 +25 (15+5+5), year 8 +30 (15+5+5+5) = maximum.
The result of implementing all 3 of these and maxing out the marketing would be a CI of 50 (marketing) + 10 (process improvement) + 10 (revenue management) + 30 (frequent flyer program). The theory behind this would be that you can't reach 100% of the customer base through pure marketing as some pax care about frequent flyer lounges, some care about getting cheap tickets or having tickets available whenever they want, and some just care about the level of service provided. Furthermore, reputations are not build over a few years, but over a decade or more. By making growth to 100 CI slow and painful, it reflects reality much better than the current formula where airlines reach 100 CI in a matter of only a couple years.
I kind of threw this together on a whim, but if you have any ideas to expand on this feel free to add them