Rotation should be fine like you said. Sanchez, Stroman, Happ, Estrada, Liriano is a very deep rotation. All they would have to focus on is maybe adding some depth behind them, in case someone gets injured.
I'd say bringing back EE could be scary, unless he runs off a David Ortiz type career into his late 30's. Though you don't want to tie in 25M per season to strictly an aging DH type player. Just look at Pujols with the Angels over the last several years. EE easily gets a 4 or 5 year deal, around 25M each season. Bautista on the other hand might take a one-year contract worth 15-18M to rebuild his value, and I'd have no problem bringing him back under those conditions as a DH.