Personally i think a C grading is pretty generous. Going by the old A-exceptional, B-Good, C-average/pass, D-bad, F-fail.
For starters you can't really judge the rookies. Until they make their debut they are unknown quantities. Some highly rated youngsters flop once making 1st grade, while some who weren't really rated forge out great careers.
Outgoing, we lost a lot of talented youngsters. While some had off-field issues their talents would be missed. We lost 2 from our starting gf side ( auva'a and keary). We lost talented youngsters in Grevsmuhl, brown, mcinnes, Carter and j.burgess. we also lost a journey man winger in Oldfield.
Incoming players with nrl experience are all, as doyen said, iffy.
Farah is our biggest signing and while he did play Origin last year he also finished the year in reserve grade. He has had a fairly bad last seasons at club level.
Rochow is a good 2nd rower, but he has played little football over the last 3 years.
Jennings debuted early in 2015 and has only played a handful of games
Cherrington debuted in 2008 and has played 19 games total. He hasn't played nrl for 5 seasons.
Kelly is coming after a stint as a backup halr at the eels.
None of those guys really inspire much greatness.
We are even going into the year without a first grade standard winger. It's likely we will either have to play a centre (jennings or goodwin) or a rookie (burns)