In your opinion - In my opinion Barnett is a carthorse who may well do a job as back up (but would be nowhere near my 1st choice pairing), Foley I've seen a fair bit of and has lots of mates who support Yeovil (No one rates him) - He will put a bit of a shift in, but there is no quality there - similar to Hoskins in that respect.
Your possibly right about Crooks - but he comes with attitude and won't be here so its pointless discussing.
I've not seen enough of Waters to make judgement really - but from what I have seen he looks a total carbon copy of Hoskins - his also done bugger all at Cambridge whilst on loan
Barnett has spent the vast majority of his career playing at Premiership/Championship level. Only 2-3 years ago he made 20 appearances for Wigan as they won L1. I thought he played well when Austin bought him back into the team for the tail end of the season also, and Austin seems to rate him. To suggest he's not good enough for L2 is - IMO of course - absolute nonsense.
Waters is good enough for L2, scored plenty of goals for Cheltenham the season before last, no reason he can't do well at that level again.
You agree about Crooks being good enough, and he may go this window, but nobody knows yet so until then you should assume he's part of the squad.
Regards Foley, I thought he was a useful player last year, and can be a good player in L2. If Hasselbaink had used him more in central midfield rather than, for example, Pereira (!) then the team might have done better in some of the matches prior to JFH's sacking. Might have provided a bit more cover for the defence as well.