Need help with a new Keeper League

[DemonDeacon]

I run a redraft league and this year we voted to have a keeper. Only players drafted after rd 3 and in the same position they were drafted the previous year. However for free agent players i set it so that they will cost a 3rd rd pick and now im wondering if thats a bit too steep. Any suggestions for free agents? All i know is that i refuse to make them 15th rd keepers (our last rd) as i dont think using the WW takes as much skill as drafting.

Thanks

PS: sorry for typos im on my ipad