Manaka's connection is what allows her to do that, but she needed the connection to boost herself and destroy the quantum timelock. Her reality warping is limited by her magic circuits, which are like no other in the world but she also has just a few.
Not really, considering that Goetia is specifically destroying the timelocks so that he can burn humanity and harvest the energy from destroying intelligent lifeforms. Throwing off the Timelock does not, by its own nature, **** the timeline into destruction.
Where is this stated though? She's the successor of crimson moon, but she's still an elemental of earth meant to represent the very earth itself. Was it said somewhere in Extra and I missed it perhaps? Where was the composite stuff mentioned? We literally see a shot of living No Name using a sniper, and hear a mention of something he did while alive.
"- Huge Scale: EX
An id_es skill. id_es skills are the inborn special powers of the Alter Egos.
Her "Self Modification" cheat skill goes out of control and activates Huge Scale EX.
It enables unlimited expansion of her size and scale.
Due to limitations imposed by the force of gravity on Earth, life forms have an upper limit on their size. Even in the sea, the size of a whale is more of less as big as it can get. The same goes for buildings, due to limitations of construction technology and financing; there is nothing that can be infinitely enlarged. This also holds true in the cyber world where the laws of physics don't apply.
All programs have a limit on their level, and no matter how greatly a program excels, in order to surpass its boundary it must separate and optimize itself."
https://www.tmdict.com/en/ki.kingprotea Translation from the Fate/EXTRA material.