I think you would be getting an upgrade in relief pitching and power however I'm not sold on getting rid of Trout/McCuthen/Andrus/Ethier for those four guys. Now, let me say why. I think if you make this trade you could get a huge spike from Tex, Hanley, Upton, and Pence OR you could completely tank your team with players that are notoriously streaky. I mean, I've had Tex before and traded him because of his .avg. Similarly, Hanley and Upton could do the same thing. Pence is pretty consistent. I say, unless you are completely desperate for the power and bullpen help, keep who you got.
I would not consider making this trade. It basically involves you giving a whole bunch of studs (young and old) for a bunch of players on the decline and some filler closers. Trout, McCutch, Ethier, and Andrus are all having career years, so why deal them?
Yuck. Andrus is great in roto leagues and you have Tulo coming back for the stretch run, so I don't see Hanley as much of an upgrade. The pitchers aren't worth destroying the solid OF featuring roto studs McCutchen and Trout. Aceves might not keep the job with Bailey coming back. Pass.