We've used Tyrano for years but with Strikeworks abandoning it and the Russian Effector not really there yet, we're at an decision moment between Renpy and another option for a second title and likely to redo our original. Nani seems decent despite the price compared to Tyrano. I like the benefits of working with Unity for porting and such. However, I see this hasn't been updated in a year so that is concerning. Unless there isn't much left to do?
Important factors for me is:
-DLCs, can it do them?
-Learning curve and is it quicker than Renpy? Comparison to Tyrano?
-Major issues, what are there? (Tyrano has had a save file issue since the beginning that they never fixed but promised to)
Want flexibility and speed of development. Renpy has the flexibility but not the speed. However, it does have a very healthy community and gets updated frequently.