You seem to think we still live in the 19th century,and that The UK is taxing the shit out of us.
You also seem to think that the GG holds any power whatsoever.
The GG only does what the PM asks him/her to do,and nothing else.
Just because we have that fancy,ceremonial "I swear loyalty to the Queen of Canada" bullshit is written there means nothing,she has a fake loyalty the crown,and a real loyalty to the PM.
The real Queen has no interaction in our politics,except maybe making an appearance at an important event,and even then she just smiles and waves.
Making Canada a republic would not only be costly,but it would server no purpose.
Canada is already free,independent,and strong.
A rose is a rose by any other name.