I am sending an email and I want to say "I appreciate your consideration for...". Would 「…に配慮を有り難がります」be appropriate?
First of all, set phrases like this can hardly be translated literally. Generally, you should try to find good examples rather than trying to construct your own sentence.
Second of all, English speakers really like to say "Thank you (in advance)" or "I appreciate" when you ask something, but Japanese people do not usually do this. What you usually have to say instead is the almighty よろしくお願いします. Unless you feel someone actually has done something meaningful for you, let's do not use thank you.
In case you have already received some response from the other party and you really feel that "consideration" is a kind one, you can say ご配慮いただきありがとうございます or ご配慮いただき感謝します.