Thomas is the gold standard. Scalia sided with the majority in Gonzales v Raich, which would have put a wooden stake into Wickard.
Yes, he is, and as someone else reminded me, he, too was criticized as being "unqualified."
Thomas's high tanding today shouls be a lesson. His qualifications at the time he was inaugurated were, at least arguably, less than Miers. But people do "grow". The heck he had had to endure has probably made him a better judge than he would have been.