If the CGI could look just like the suit, but not have any of the physical limitations of the suit, like slow and cumbersome movement and stiffness in the body in parts that are not puppeteered, that would be nice to see. Nice seamless integration with real backgrounds and human actors, or even cgi human actors would also be cool.
I'll use the remake of Clash of The Titans for an example. Given the make overs of both the Krakken and Medusa, I'd much prefer Medusa's CGI rendering than The Krakken's. It moved better, while still basically looking like the original stop-motion incarnation, unlike the revamped Krakken.
When it comes to which Godzilla suit, I'm sure CGI could make just about any interpretation look alright, nice and alive.
If it can do that and make the monster look like it was really there, that immense, moving with a real sense of weight, Like Bahamut, Cloverfield or GINO, than I have no problem with using CGI. Either that, or the cities and backgrounds would need to be digitally manipulated to add the illusion of size to an actor in a monster suit, real time damage to the suit would have to be CGI and humans and vehicles would have to be digitally miniaturized and synched up to interact with the motions of the live action monster suit actor.