Worth Trading or Settle With Current Team?

[Salad Fingers]

Wondering which of my rookies are keepers and which are worth upgrading? I only have 5 trades left and 55k in the bank.

Side is:

Backs: Mackie, Hodge, Fisher, Milburn, Bock, Adcock, Goddard
Reserves: Broughton, Pratt

Mids: Ablett, Mitchell, Gibbs, Bartel, K Cornes, Rich
Reserves: Hartlett, Swift

Rucks: Cox, Jolly
Reserves: Pyke, Spencer

Forwards: Didak, Pavlich, Goodwin, Gia, Deledio, Franklin, Skipworth
Reserves: Sidebottom, Daniher

I will be sitting on my trades for a few weeks as I am undefeated in my league and have 3 of bottom 4 sides to come. However not sure if Skipworth and Rich are keepers and if not, who I should get in. My trade out options would be Hartlett or Sidebottom to free up cash, leaving me with 4 trades to complete my team. Happy to keep Buddy as just about everyone in my league has picked him up at his current price so I am not losing out by having him.