"Preferably near the equator to have earth's spin assisting you."
TBH that's a bit of a myth.
When you break down ascent losses you find the difference between the Ariane 4 launch site (which was also Guiyana) and the Space Shuttle Florida) site is a whopping 18m/s.
OTOH by having a better ascent trajectory (which Shuttle had) it lowered its "gravity losses" compared to A4 by 344 m/s
The big with with a rotating earth comes when its compared against a non-rotating earth.
Which would be a bad thing for all sorts of other easons anyway.
Biting the hand that feeds IT
