Terraforming projects to convert gas planets into stars
If there was enough mass in the gas giant to turn into a star it would usually already have done so. Jupiter for example is approximately 1000 times less massive than the Sun.
You're looking at needing multiple gas giants (even super-Jupiters) to get a useful star out of the far end. And you've got to contain all the gas/plasma whilst you ignite the "new star".
That's far beyond anything that could remotely be considered akin to terraforming.
And please give us some kind of Star wars centerpoint station - a station that can move whole stars / planets maybe also star systems from afar.
Ofc this would have to be REALLY late game and you couldnt use it on enemy systems fir example because you have not enough telemetrical data or so.
Moving stars and planets - and especially moving star systems would play havoc with the game. Yes, we already have projects that rebuild systems (ringworlds in particular), but since stars and their locations are part of how the galaxy is structured, and moving them would involve having to remap any distance calculations involving that system (and redraw the hyperlanes), it's probably beyond technical possibilities.
And we NEED a way to invade other dimensions like the unbidden do. For example it would be an idea that you would have to be psionic ascensioned and the unbidden must have been killed. Then you can research some technologies or get an ap or whatever to invade another universe
No, we really don't.
Firstly that means that only one ascension can do it. If it a particular end-crisis has happened.
Secondly, what do you get to take to the new galaxy? How built up do you have it be? How long do you want to sit and wait for the game to simulate another galaxy for - or would it just load up a pre-set (or one of a number of pre-set) "advanced" galaxies?
But no. Once you've won, you've won. Start a new game, try something else.