Hi!
I have just started using Zwift. It’s a great app for me, but it has already reached its limitations which seem that can be resolved quite easily. So the problem is my Novo Force and MTB bike. I have max gear (3x7) and with cadence 90 I generate 230 watts on trainer setting 3. So if I will develop my performance the only way of getting higher power is to increase cadence, and I cannot train with cadence 120, its quite sick. I would really like to change this resistance to ex 4 or 5 but I can’t because then I will have fake power reading. From what I suppose the only thing that developers need to add are another power curves for these remaining settings. Am I wrong? If not I really cannot see a reason why this is not a priority already, it would be a fantastic improvement especially for beginners with MTB bikes.
The next phase of my idea would be dynamic changes of resistance during rides. For example, when I approach a hill app could tell me to change resistance for example to 5 or even 8. Then I will have to change gears or decrease my cadence and use more strength. Accordingly when going down the hill resistance could be changed to 1. Training would be more interesting and interactive. Of course not everybody wants to keep playing with resistance so this feature could be optional, but hey, it sounds terrific to me 
Please let me know if anyone would appreciate these features. Maybe we can convince Zwift team to implement it soon. Have a good ride!