Draft year SC averages
I've put some of the averages of the relevant rookies over the last two years whose SC averages I had into a table. 2018 draftees are from the 2019 Prospectus, 2017 draftees are from here. SC averages of rookie draft selections weren't in the 2019 prospectus (I couldn't find them but let me know if they are somewhere).
I've put a * for Caldwell and Butters as the player description suggests they had an injury affected game in the U18C.
On Butters, he had a shoulder injury in the final game of the U18C, but played four games in total. Even if you assumed he had a 0 in the final game, the other 3 games would only give him like a 75 avg for the U18C.
Caldwell appears to have gotten injured in the first game, so had 32 from one game.
^ for Burgess as it referred to his "ranking points" in his description for his games as a KPD and KPF - not sure if "ranking points" meant SC.
Hopefully this helps somewhat with the final rookie selections, or with rookie downgrades! Rookies who played in JLT but were drafted before 2017, or were from rookie drafts (ie: Atkins) are not in this table as I didn't have their past averages.
JLT Rookies 2019
I've made a simple table with all players under $250k who played 2 games in the JLT and had greater than 50% TOG. Players with greater than 70% are highlighted in green (so I guess the rookies in white are the ones with questionable JS?). Rookies are sorted by SC per 80%TOG.
JLT Bolters 2019
I've made a table of "JLT Bolters". I've cut it off at 100 on the SC per 80% TOG scale and only included players who had at least 50% TOG in the JLT and played two games. Green highlighted players had at least 70%TOG in the JLT (so their SC/80%TOG probably haven't been boosted by scores from limited game time).