Remember that if you power up, it's a long-term investment (you can turn it to STEEM at a rate of ~1% per week). 5000 STEEM = 5000 STEEM POWER.
Curation rewards will depend but I think you can expect at least 10SP per week. My ~1500SP give me from 3 to 10SP per week in curation rewards - but it is dependent on what I curate, obviously
RE: Investing long-term with Steem: Time as an overlooked parameter