I tilt to small and value myself and own a lot of those funds. That is a fine portfolio and so is your original one.
You don't need to buy individual bonds. You don't gain much from treasury bond funds since there is no need to diversify among issuers with treasuries but the fees are very cheap and like you said it makes it easier to rebalance.
Vanguard Small Cap Value has quite a large amount of REIT stock in it (it was 15% REIT a few years ago) so keep that in mind if you ever want to include those. I personally don't have a specific allocation to a REIT fund just because of this.
Like I said Total Bond Market is an above average choice. But in times like 2008 when all risk-assets crash together there is a flight to safe haven assets like Long Term Treasuries. Since you are young the purpose of your bond allocation is not to sweep interest payments to a spending account. Its purpose is to provide diversification. If interest rates go up long term treasuries lose a lot of value. Even though you aren't holding individual bonds if it helps your peace of mind you could always sell your fund and buy a zero coupon bond and hold that to maturity to recoup your initial investment.
I am 27 myself and I am about 85%-90% stock using Vanguard and DFA funds (headed by the academics who first published about small+value tilting but these are hard to access and luckily I have them in my 401k). Then I have individual 30-year treasuries to diversify (which have done well in the last year like I said), and a small splash of the Pimco Commodity fund since the risks of commodities complements duration risk very well. Adding a small splash of commodity exposure allows you to take on more duration risk. But I've been hammered on this with the falling oil prices.
So I have all high-volatility investments. I don't hold any stable investments like short-term bonds (I do have a sufficient cash cushion in my bank account).
While common wisdom is that you adjust your risk tolerance by adjusting your stock/bond allocation, it is better to borrow money to invest if you want to be more aggressive, or hold cash & other low-volatility assets like short term bonds in addition to your investments if you want to be conservative. I don't buy on margin and instead I chose to take out a 0.9% car note with 0% down instead of buying my car with cash earlier this year.
Your portfolio is fine and how much you contribute to it is much, much more important than little optimizations. Your time is much better spent looking to increase your income but this has been a hobby for me so if you have any questions let me know.
Also try /r/portfolios too