First off - nice team.
I think Valverde, Beckett, Quintana, and Fister are your most droppable.
However, this is a gamble. I think Youk will have a monster second half to prove everyone wrong and will really like hitting in US Cellular. Pretty nice hitting around Dunn and Konerko too.
But this is just a hunch. Valverde is still technically the closer in Det when he comes back. I think your depth is SP. I am not sure about Beckett's injury, but his name makes him valuable for trades. Quintana is not owned YET in my 12 team league, but I think that may change soon. So, he is probably the safest to drop and then pick up if you ask me.