I just fininished Carrock, am moving onto rosegobel, and have the next two packs in the mail 
I managed to beat the carrock solo using a mostly Rohan themed deck. I went to play it solo again, this time trying to focus on an eagles theme, and was promptly devoured by trolls. I'm sure its half build, but it seems that there just wasn't enough support options (as of C@TC) to do such a heavily themed deck. I'm curious, with the later expansions, how possible is it to play themed decks? I notice quite a few "subfactions"... dwarves, gondor, nobel, king, etc. I know Kazad dum gives dwarves some lovin', but I heard despite all of the new cards, dwarf decks just aren't really possible yet.
How are the other subfactions doing? Are any of them really feasable? I can vouch for roherum, at least with my small amount of experience and luck, seem to be a decent build (if not just for solo games).
Also, do you think we'll get more istari? The game seems to have picked a timeline, so I don't suppose we can ever hope to get a good sauruman the white (unfortunate, i'd like to see a pre-fallen version of him).