The meaning "ruler over" for KEFALH does not mean that the husband could not "nourish" and cherish his wife as Christ does the congregation. The husband in his role as "head" is not supposed to be an autocrat or totalitarian ruler.
BGAD says that KEFALH, when applied metaphorically to Christ and others, denotes "one of superior rank." Louw-Nida makes similar observations. So if we are going to contravene the wisdom of the major lexica in this regard, I think we will need some powerful evidence to maintain such a contravention. Yet I am not so sure that any passage from Ephesians serve the purpose.
For instance, Markus Barth (Anchor Bible Commentary on Ephesians) makes this observation:
"In our translation [of Eph. 5:23], these words are marked as a parenthesis which complements the Messiah's title 'head' with a more specific and extensive description. To use a paraphrase again, the parenthesis says in effect, 'He, and he alone, is not only Head but also Savior'; or, 'He proves Himself Head by saying'; or 'His work of salvation includes his dominion over the church.' However, this interpretation and its variations have always been and still are challenged by a sizable group of commentators who believe that Christ is not the only one predicated as 'savior.' They hold that in a subordinate way the husband, too, is the 'savior of his wife'" (Barth, Volume 34A, pages 614-15).
While I will let others haggle over the idea of the husband being a "savior" of his wife, the main point I want to make with the quotation from Barth is that the parenthesis in Eph. 5:23 functions as a clarification of Christ's position as KEFALH of his own body, the Christian EKKLHSIA. He is KEFALH (according to this passage) insofar as he's Lord and Savior.