You cant call this car Electra, it's not the top of the line car, Electra, Roadmaster or Park Avenue would have to be reserved for the Lucerne replacement or a car above that.
Electra was typically a larger car than the historical Invicta no?
They were both full size, similar relationship that the LeSabre and Park Avenue had through 2005, when the Lucerne "combined" them into one model.(really a LeSabre, the Lucerne is not luxurious enough to replace the Park Avenue IMO) I think that there is room for both a large FWD Buick and a large RWD Buick in the line up, the FWD can compete with cars like the Sable, Avalon and other while the RWD Buick sedan can go up market.
Regal is a good name for this car, it has good recognition and never really had a "bad" era, plus there is a little Grand National magic that rubs off on the Regal name.
Century would also be a great name, Buick heratige dating back to the 1930's, good reputation for solid reliable cars, too bad that is does have blue hair stigma from the small whites and wires boxy 80's Centurys.
Invicta, another good name, it replaced the Super in the Buick line in 1959, it did not last long, it was gone by 1964, so it is virtually a brand new name for Buick, hardly anyone in the general car buying public would have heard of it before, so it has the "no baggage" bonus.
Wildcat replaced Invicta for 1964, I really like this name, though I dont know if I would use it for this car, I would rather see it go on a special editon of the Buick Zeta with an LS9 or something.