Lets say this year and next two years.
C- This year, sox. Next year push or slight + for Cubs.
1b - I'm partial but i say Abreu for all. but reality is it will be andrew vaughn at 1b and abreu at DH.
2b - Madrigal looks great and horner is a gamer, we can call it a push right now.
3b - I'll take moncada over bryant for now and next few years due to production/defense/actual cost of the player. moncada has a very team friendly contract for 4 more years.
SS - TA, due to contract and bat.
LF - Eloy.
CF - Robert.
RF - for now cubs, but if Grandal is forced to DH more, its likely andrew vaughn is tried out in RF, he's already getting reps there in Schamburg.
SP 1 - Darvish is
**** awesome. however, he's older and loses his "feel" often. Giolitto is younger, and he's a stud himself.
SP 2 - I'd say its a push.
SP 3 - Dunning over lester
SP 4 - Cease, his walks are a problem but none of the players you mentioned other then mills has his upsode, age or cost control on his side. esp when considering the next 2 years.
SP 5 - Wsox. likely a FA signing.
Bullpen - This is where it gets fun. The Sox have done an excellent job putting a fantastic bullpen together. i'm not a fan of Colome but he's making it work with smoke and mirrors. Adding Crochet to the BP I think gives the edge to the Sox.