"HillaryCare" did not exist at the time Perry wrote his letter. It had been announced she was looking at the topic of healthcare reform, and he wanted to make sure she did not neglect rural Texans (which was sort of his job). Once it was clear what she was up to, Perry apparently hated it as much as the rest of us.
I think he can be criticized for believing it was even possible for Hillary to come up with meaningful reform, but I don't see how can be tagged with supporting the HillaryCare proposal that actually emerged because based upon what I have read, he clearly didn't.
He didn’t say he thought she would come up with good ideas. He wanted to strongly insist she take into account the constituents he represented. He started with boilerplate niceties, because that’s how you start official letters from government officials to government officials.