I wouldn't do it. Braun's SB would be hard to lose for you, since your only other real option for SB is McCutchen. Plus, your SP seems pretty deep to me. Honestly, your top three are awesome, and your support pitchers are all better options than Romero. Plus, if you really want pitching, you can probably find someone comparable in the free agent pool. Not worth it to me.
I agree your 3B could use an upgrade, but Seager is still currently a top 100 player in yahoo. If the trade is essentially a 1-1 with two plugs, you lose out because you trade the better player. I'd look at the trade in terms of player for player, without factoring in position, because, realistically, both start all the time and contribute into the same stat categories. If Bautista only qualified at OF, would you trade Braun for him then? The answer is no, you wouldn't. Turning a position of strength into a position of (relative) weakness is not a good strategy, and that's what would happen here. The end result would be the same: you would have a strong 3b and a relatively weak OF rather than a strong OF and a relatively weak 3b, plus you lose SB, which you need. The only way I would do it is if I could get more than Bautista + Romero.
I like this deal for you.....it is tough to part with Braun but you get Bautista back which Braun plays OF only and Bautista has the OF spot and also is 3B eligible.....plus the fact that Youk is about half past done I see Romero as a freebie throw in so....
I say go for it and a nice deal for you....(Braun and Bautista are about even in my book)
I wouldn't do it, I would rather have Braun over Bautista, I agree with SonofaPitch, I wouldn't trade Braun for Bautista straight up, it just seems like you are making one position stronger by making the other weaker, I don't see it being all that big of a help to you especially if Seager keeps playing well.