Do the Right Thing
I kind of look at it this way, you're basically asking if you should respect the community that gave you what you have by becoming more involved (powering up, upvoting content, being social) or if you should just enjoy what you've earned and quit.
To me, I think this sounds like a rather selfish post. I mean, do what you will, to each their own, but for me there would be no question. Community is the answer. Unless you've invested heavily to buy a new computer or whatnot to create the writing you've created, then you certainly cant be out too much more than the power it cost you to upload your content. Give yourself some reward by cashing in some steem dollars, and reinvest the rest.
If you reinvest, and steemit eventually fails, would you be utterly heartbroken? Maybe a bit dissapointed that you didnt cash out earlier, but I doubt you'd feel a crushing sense of defeat. If you power down now, and steemit fails anyway, then those hundred dollars a week could become pennies anyway at almost any time.
But if you believe in the platform, you'd reinvest. You'd power up, become someone who does more than just ask simple questions to receive thousands of dollars worth of upvotes. You could carve out a real niche in the community, and be that part that encourages others to join, instead of one of those that encourages others to cash out.
Lead by example, and BE the example you would want to see. So I answer your question with a question, what would YOU want to see from someone asking the same question, ESPECIALLY if you were a minnow, or a user looking to join? Would you want them to support the community, and thereby support you and the platform you post on, or would you rather see someone make a few quick bucks and leave, giving you little hope and even taking away the overall drive to keep putting in the time and effort to create thoughtful, innovative, and unique content?
Minnows like myself are watching, to see what example you choose to lead by. I cant speak for everyone, but I hope you make the right choice.