401K Investment Options. Small Cap versus Large Cap

Hi Jeremy and Personal Finance Club folks,

My employer offers a 401K plan that has 4 index fund (all have similar expense ratios; some have higher turnover ratios than others, but overall pretty similar) options to choose from:

  • Vanguard Institutional Index Instl Pl (VIIIX)
  • Vanguard Small Cap Growth Index I (VSGIX)
  • Vanguard Developed Markets Index Fund (VTMNX)
  • Vanguard Small Cap Value Index Fund (VSIIX)

My questions are:

  1. Should I invest in all 4? If so, should I put a higher % in the US heavy Index Funds versus the International heavy index fund (VTMNX)?
  2. Is there a reason I should not invest in all 4 Index Funds?
  3. For the US heavy index funds, how do you know how much percent to invest in each? Should large cap and small cap be treated the same/differently?
  4. With these options in my 401k, should I go more bond heavy in my Roth IRA and brokerage account? Or will a target date index fund suffice with balancing things out? I am 33 years old.

Thank you!!