Your asset allocation looks decent. The biggest issue I see is that your international equity allocation is way too low at roughly 25% of equities. I'd increase that in order to be better diversified under any circumstances, but especially now when U.S. markets seem significantly more expensive than international markets. If you're unsure or uneasy about this, consider 50%, as in 50% U.S. and 50% total international, or 50% U.S. and 40% foreign developed and 10% emerging markets (percentages given as a portion of equities, not of the entire portfolio).
Having some international bonds is a good idea and not unusual. Most Vanguard balanced funds have been including them for years, for example. Most people would agree that (unlike with stocks) you're better off owning currency hedged foreign bonds. There's really only one good investment vehicle currently available to U.S. investors for this asset class: the Vanguard Total International Bond Index.
Including REITs and TIPS and even a small amount of gold is also a good idea in my opinion. Tiny 1% allocations will do absolutely no harm but probably not much good either. In this category of assets that could provide some protection against inflation, I'd consider something like 5-15% REITs, 5-10% TIPS, and, if you're able to stomach the volatility, 5% energy stocks and 3-5% gold miner stocks or gold.
If you decide not to allocate a sizable chunk to the assets mentioned in the previous paragraph, you might as well go with a balanced fund (plus some cash as an emergency reserve) and save yourself the trouble of having to manage a portfolio. That's because your asset allocation would be extremely similar to an aggressive balanced fund. The Vanguard LifeStrategy Growth mutual fund would be a good choice, or if you want to use a brokerage, the iShares Core Aggressive Allocation ETF. I wouldn't go with target retirement funds as they decrease the stock allocation way too much as you get older.
Having a few months' worth of expenses in cash or something very similar is a good idea in my opinion. If you can store it safely, I'd even suggest keeping one month's worth of expenses in physical cash, just in case your financial accounts get hacked or banks run into temporary issues with their infrastructure. However, I would calculate the required cash position solely based on my expenses and I would let it become a smaller and smaller percentage of my net worth as my savings grow. In other words, don't consider your emergency reserve part of your asset allocation. If you feel you really need the stability that cash provides in a portfolio (as opposed to the cash functioning as an emergency reserve only), then consider high quality short-term bonds.