However, if your tweet hadn't gotten traction, and if Namecheap hadn't been proactive, you'd likely have never gotten the domain back. I mean, you had the Namecheap CEO on the case! And for a business losing a domain like that, it'd probably be fatal.
I get that many think that Americans are hugely too litigious. But there is the argument that there ought to be compensation for damages.
You say that "[t]he primary loss I suffered was in terms of time". But arguably your time is worth something. Such as your customary billing rate, times three.
Edit: Or just send them an invoice. At perhaps 50% over your customary billing rate, given that it was a rush job.