$3k of that was this quarter's Chase Freedom, others were Paypal gift cards bought at ~4-5x points. There were a few Visa GCs from various sources. The rest was good 'ol Freedom Unlimited @ 1.5x points.

I would agree that there's a lost opportunity cost of investing, BUT, that $9500 is over 2 years. I normally only have $1k-$2k out on loan at any time on Kiva. Remember, MS with what you can afford / are willing to lose. There's nothing saying Kiva won't just close their doors one day without notice. The same is true with any other MS option -- one day the magic stops, hopefully with enough warning to be able to cleanly liquidate back to cash.