Gase giants terraforming

My opinion is, if it should be necessary, it will be better to add a Phase IV technology which enables building floating habitat above the gas giants. It may have less effect than turning a gas giant into a concrete planet, but will be able to reach a balance between your wish to fully utilize the planet and other people's concern about breaking the game balance.

It would be fine too, and more balancing. But we're talking about SciFi here, and what kind of SciFi is this, if it have'nt a mind breaking technologies and breathtaking deeds? 

Floating habitats... then how do we colonize a GG at the first place? I guess (and I'm gonna check it right now) that this technology is allready took it place in a Phase II or III. Phase IV technology - or even few - yes, that's how I imagine this. But it should be a technology(-es) for changing the wery fabric of GG or at least - changing it's type.