Do you think it would better if we went back to a top 5 finals series instead of a top 8. No team has won a premiership from below the top 4 for 22 years.
Teams 5 to 8 have to win 4 rather than 3, but after the first week the two left from 5-8 are no worse off theoretically than the two losers from top 4 (well, they play "away" but that doesn't mean much, especially if it is a Sydney home game).
The teams that skip a week rarely both make the GF (last year and 2012 I think are about the only times in recent history), but it is usually the other top team that lost that makes it through (Warriors a noticeable exception a few years ago, though the finals system was a bit different then).
Since the top team that lost is not really any better placed than the bottom team that won, I'd say mostly the teams outside the top 4 don't win is that they are just not very good, most years, compared to top 4 teams (most years there are 2 or 3 dominant teams, sometimes 4).
So I think a top 5 would give better games and skip the crud, but certainly would not be commercially viable in the modern TV sales era.
This year, one team is dominant, but the rest are all similar IMHO, so there is a reasonable chance any of 2 to 8 could make the GF, though obviously 2 - 3 still have one less win to make and should be favoured.
I just don't think there is a gulf between say, 4th placed Eels and 7th placed Panthers, this year. I guess this means this year, most finals should be sufficiently unpredictable, which I guess is a plus for a top 8 system, if you can have a lot of finals that are not pointless walk overs.