Others have given you good advice about stock picking and valuation - don't. I'll echo that, but I want to address something else.
2. I have 90% of my money invest via Vanguard. Is this unwise?
If your taxable stash isn't that big, you need an emergency fund. The actual amount there can decrease as your taxable stash grows, so if 10% isn't enough for comfort, maybe that needs to increase.
Keeping all of your investing assets at Vanguard is fine. The short answer is that each of the mutual funds owns a share of the company, and your ownership of their funds is part ownership of Vanguard itself.
If you're worried about keeping all your eggs in one basket - as if Vanguard could go belly up, the way Enron did or something - check out the Bogleheads' wiki article on
Vanguard Safety. The short story is, you really don't have anything to worry about.