[noun] + もさることながら
もさることながら means "X, of course, but also – and more – Y". It follows a noun: the speaker grants that X matters or impresses, then turns to Y, which is the real point of the sentence.
It takes a noun only. To use an adjective or a verb, turn it into a noun first: ×おいしいもさることながら → おいしさもさることながら.
The fixed part comes from classical さる, "to be so": "X being so as well, …". It has nothing to do with the ながら of "while doing".
もさることながら belongs to writing, reviews and speeches. In conversation もいいけど or だけじゃなくて does the job.