This is now two separate but related issues:

1) Importing max/MSP into Pd + cyclone

2) Maintaining backwards compatibility for Pd patches written in Pd + cyclone

The differences are not trivial. If it were just importing max files, then the problem is now in the translator, and the obvious solutions in my opinion are the ones you just mentioned.

But that would break files that were patched in earlier versions of Pd+cyclone in the first place. In this case, I think that [pow~] should throw a warning for a while. And because Pd has a "find" feature it will not be difficult to find instances of pow~ and change the connections, or to make a little abstraction with crossed inlet~s called max_pow~ or whatever you like and then find and replace. Cyclone could even come with another utility to do this automatically -- anyway I think backward-compatibility is the lib's responsibility, not Pd's.

Matt