The first thing to consider is the capacity and performance of the devices. As you say, the target devices will be the following:
These devices are capable of running a brutal number of objects with physical behaviors. First by hardware factor and secondly by the OS.
Now think, with C2 you will create the game environment (easy and fast). You'll export it as HTML5 and then using a service like PhoneGap or CocoonJS .... you'll need to transform the result into a compiled native code.
In this process, the objects will be recompiled using their frameworks and extensions (totaly compatible with review process of stores). The web environment will be converted into a native WebGL or Canvas environment.
Therefore, you can get the same performance you've seen in other games running on those devices with these OS.
As already mentioned, get 60FPS in these conditions is entirely feasible