A brief statement against retirement date funds:
You pay higher expenses for lower fluctuation that you shouldn't be worried about at all with a 35 yr investment horizon. You also unnecessarily park a lot in low-rate bonds. To use the retirement date funds, you can tweak how aggressive or conservative they are by your retirement date relative to the current year. If I ever used one, I would set it to retirement in 2150 to get the level of investment aggressiveness that I prefer.
Unfortunately, you also don't... really have much choice.
Fees should be under .25%. The options here are weak. That's ok if you diversify over your total portfolio and lean on VINIX in this one, but unfortunately, the TRowe funds and VINIX are the only ones I would use here. VINIX is one of the better offerings but not the most diverse Vanguard offers. I would put a Roth IRA at Vanguard after you max this, and get a better mix of index funds.