I agree quoted strings in queries would be nice. There are some technical challenges in handling mixed queries where some terms are quoted and others are not, though.
Well, no. SearchYC has no revenue. I maintain SearchYC and host it out of a box in my closet as a service to the community. It doesn't make any sense for me to commit to do "whatever it takes".
That being said, with a few hundred dollars worth of hardware and some software changes, SearchYC should be able to gracefully handle a couple orders of magnitude more traffic.
As it stands, SearchYC doesn't get enough daily uniques to justify beefing up the system. Frankly, SearchYC was an experiment in how quickly I could learn a new technology (RoR) and build a system. I was completely expecting someone to come along a few months later to make SearchYC obsolete. It's been 2.5 years, and I don't think that's happened yet.
SearchYC doesn't scrape the user pages containing the account creation date. We could generate numbers based on days since the user's first post, though.