You asked if they improved the side, not if they were better/superior players.
The "points total" stats quoted kinda show that they didn't really have much of an impact on results overall.
My opinion, FWIW, is that the new players are better in certain aspects of their game but worse in other aspects
ie - Wan Bissaka is a better defender but adds less of an attacking threat than Young/ex wigan bloke who's name escapes me
Breeze Block head may well be a better all round defender than Smalling/Jones but has just as many unforced errors in him that it's pretty much a like for like swap.
Goofy has some skill but appears to have "polar" games (great or invisible when he's not up for it, no in between)
No real change, IMO.