Yep
Though it would probably be more accurate to see how the potential abuse changes past rankings.
For example Luffy was always No.1
Zoro has five No.2 placements and one No.3
Sanji has four No.3 placements and two No.4
So in average Luffy is pretty much guaranteed No1, Zoro No2 and Sanji No3 based on the old system which lacked this potential of abuse.
No, it isn't change of System only, the Votes were always exclusive to Japan, now it's Worldwide, we will see big changes, possibly huge ones
Zoro was always close second to Luffy however when it comes to Worldwide, he could take the win this time, especially since we are in Wano Arc & he had lot of cool moments
Sanji will always take the 3rd Spot, i don't except any Character to surpass him especially after he got WCI dedicated for him & he also had some cool moments in Wano
IMO Ace & Sabo & Law will always be present in Top 10
And i expect this time, Marco to hit Top 10, after all the guy was Top 20 in Japan even though he was absent in Story
For the rest of Top 10 & 20, i expect the rest of Straw Hats, Kid, Popular Shichibukai (Hancock, Mihawk, Doffy, Croco) & Shanks to be present
I think Katakuri could also be in Top 20, i see tons of his Fans everywhere
As for Kaido, BM, Oden, Roger & WB, i expect them to be higher placed than we last saw in previous Polls but not sure if they can hit Top 20 (BM doubt it but rest very possible)
Killer & Drake will most probably be in Top 30 i think since they are finally being relevant
Cavendish & Bartolomeo too have some decent fanbase
And ofc, we will see the usual females (Vivi, Shirahoshi, Rebecca, Perona, Carrot ... etc)
As for Marines, i think Smoker, Tashigi, Aokiji, Koby & Garp are the most liked ones (Maybe Fujitora too)