I can't see the point of changing Ferguson Street. Sparks to Williamstown Beach and Williamstown cross it, and that's your lot; no V/Line pass and no freighters. You don't have the booms down while a succession of trains go by a la Springvale for example. And Williamstown itself is almost an island; it's on it's own sort of peninsula, and you don't go through Williamstown to get to anywhere else. The crossing just doesn't carry heavy traffic.
On top of that, it's one of the safest State ALP seats, so there's no need for pork barrelling.
The traffic using the Ferguson Street crossing is not light and is getting heavier as Willy's population is becoming more dense. It's also the only road that takes Willy traffic to Altona and beyond to Werribee and Geelong. The crossing is at the location where 8 streets / roads converge with complicated roundabouts on either side.
The only solution if you are to remove is to raise the rail with a new elevated station at North Willy ala Carnegie. Is it worth it? Well, if you removed Kororoit Creek Rd crossing you should remove this one. This has more trains than Kororoit Creek Road.
Don't even think about Light Rail, why spend a squillion $ when you have something fit for purpose already?