That's a great question, but I'm not sure I have good investing advice for you. There are so many different approaches, and I've been trying my best to soak it all up over the past couple of months. Another thing to consider is how holding VESTS gives you newly created Steem Power. STEEM itself gets diluted, but Steem Power increases based on the distribution numbers here (1M VESTS will equal more and more Steem Power as time goes on): https://steemd.com/distribution

To me, I think long term value is in Steem Power, assuming the platform survives and thrives. I might be wrong there, but what some call the "interest rate" for having VESTs is quite high right now and will settle down in less than a year. SBD, on the other hand, also give you interest but (hopefully) in a pegged asset, unlike STEEM which has been free falling or Steem Power which is illiquid and requires 104 weeks to fully divest. So yeah, I'm not really sure. Some days I think powering up everything is the way to go. Other days I think I should have held on to more SBD. Still other days, I wish I had powered down and cashed out some Steem for BTC so that I could buy in much cheaper later.

There are a lot of posts about theory and such, but I think I've learned the most from just asking questions in the Steemit chat #price channel.