This, of course, assumes that 1-4 will be some combo of Davis-MKG-Beal-Robinson. And that the Wiz don't take MKG. Given that our "worst case" scenario is probably Barnes at 5 or 6 if 3 teams jump the lottery, I think the best possible outcome for the off-season is to grab Davis/Beal/Robinson and do anything possible to add Batum via free agency (i.e. paying him enough that Portland won't match).
I look at it this way: the Wiz already have 2 current "core starters" and either 4 or 5 "core rotation" guys. I think they have to get 3rd and 4th "core starting" pieces this summer through any means possible, in order to prevent the rebuild from stalling or falling off the rails. Batum seems to fit a need almost perfectly, a non-selfish 3-and-D energy guy with good starting upside, excellent advanced stats and doesn't need the ball.
Assuming Lewis is bought out for $13m and Baltche amnestied, that leaves the (hopefully) new GM about $18m of cap space to work with. I see the current roster having:
1 - Wall
1 - Mack (this is a maybe)
2 - Crawford (for at least 1 more year, longer if he reigns in Chuckford)
3 - Singleton/Booker
4 - Booker - I see him as the 6th man, playing either forward position (if we draft Beal hes a starter by necessity). LOVE Booker, don't think he has the size to play the 4 long-term next to Nene as a starter.
5 - Seraphim (Somehow I have talked myself into him a solid 4th big)
Role player/Deep Bench/Too soon to tell if they will develop
Mason (or similar replacement)
2 min-contract vets/D-leaguer's
Because I see the roster that way, I think the Wiz have cultivated a solid rotation, it just needs starters to play the bulk of the minutes at the 2-3-4 (or 5, if we luck into Davis and Nene can play the 4). Since the 2 best values in the NBA are a superstar on a rookie contract and a more-than-max value player on a max contract, I think if we win the lottery they could damn well give every remaining cent of cap space to Batum, and use the mid-level to add a quality veteran SG. I think Batum's value to the Wiz goes down a bit if we get Robinson or Beal, but with any of those players I think overpaying a bit for his defense, shooting, IQ and flexibility (can play the 2 if we went big) would be a great idea and fills multiple needs. He seems a perfect fit for this team, and SG/PF could be addressed with next years draft.
Even contractually, if you gave him a big 4-year deal, he would be off the books by the time you had to pay this years first-rounder his 2nd contract (assuming this pick works out well!). I know Portland is likely to match most offers, but I think overpaying a bit may end up worth it. A starting lineup of Wall - Crawford (or MLE Vet) - Batum - Davis/Robinson - Nene with Crawford/Singleton/Booker/Seraphim in rotation doesn't look nearly as bad on paper, and with 1 more year of development (and *crosses finger* the "third year jump" for Wall and maybe Booker) this team could be dangerous starting in 2014.