Multiple vanguard fund diversification

[t-mmm-reader]

I am looking for any advice on how to best diversify across 4 vanguard accounts. 2 Roth IRA's, 1 traditional, and a joint account (for general long term saving). I am pretty well familiar with all the different funds they have available now, but narrowing it down to pick for each different account is proving to be somewhat challenging. 

[Enigma]

I try to keep the funds pretty simple with Vanguard myself.  My 401k Vanguard account sometimes didnt give me the options.

There is no need for 2 ROTH Vanguard accounts.  If I was in your shoes I would rollover one into the other.

VBTLX - Vanguard Total Bond Market Index Fund Admiral Shares (~30%)
VTSAX - Vanguard Total Stock Market Index Fund Admiral Shares (~70%)
VGSLX - Vanguard Real Estate Index Fund Admiral Shares (FUN)