Ginger uses her sexy approach to influence many of the visitors, especially the cosmonauts & Kincaid which she then takes them to the other side of the island for a private swim and possibly more, as a distraction ...

She is often purring up to Gilligan, the skipper & even the professor when she desires something they have or control.

To me it seems odd that she is mostly portrayed as glamour gal actress but then gets parts written into the script to act kind of sleazy (?) You think that that image is how Hollywood viewed glamour gal actress and so it's reflected ?

Though I do enjoy her sexy seductive acting - wishful thinking !

Nothing like that happens regarding Mary Ann ... or does it ? again wishful thinking lol

Do Mary Ann or Lovey ever flash some sex appeal ?
I don't think I have ever even seen Lovely's knee LOL

Does Mary Ann act sexy when she banged her head and thought she was Ginger ? or when the Mosquitoes were visiting ?

I really like when Ginger tries to teach the professor how to kiss ! (for their movie and when Erika Tiffiany Smith (Gabor) is visiting !

This sitcom has many classic comedy moments - good casting, writing & acting as well - I can't help but like the entire cast

There's one thing that you left out when it came to Ginger acting sexy to get something she wanted:

It never worked.

Tina Louise was a truly beautiful woman. I’ve seen photos of her online in her young prime and she’s a knockout. I wonder why she didn’t star in more theatrical movies.

I think that the first season episode "They're Off and Running", Ginger seduces Gilligan into telling her about Mr. Howells turtle. Ginger also seduces Gilligan into giving her nine feet of rope that was intended for use by the Skipper. That was the first season episode where they were all building themselves huts.