If I had 17 years, and know I wouldn't need the funds barring a major calamity, I'd be pretty adventurous with the money, XLK is a decent place for half of it anyway.
I might dial back some on the other half, but I'd probably split it between a health care ETF and a dividend ETF, I broker with Schwab, so I'd use theirs, but any of the others should be fine too.
I would avoid the funds that reinvest your monies according to your retirement age, I think they are gimmmicks. BUT, I would change the above as that 17 years became 5 years.
Rebalancing my portfolio is where most of my energy goes. I was lucky enough to buy quite a bit of Apple a while back and the runup made it into too large a percentage, so I was unlucky enough to sell part of it, and now it has run up again. Anything I might need in 5-7 years is liquid.