Truth be told, whether or not we use the Wyoming rule or not it all pretty much comes out in the wash, which I think may have been YamatoTwinkies point. Any division of the states into integer numbers of representatives is going to result in winners and losers, and those winners and losers are going to be concentrated among the less populated states because rounding errors are a larger proportion of the overall representation. Under the current system, the big winner is actually Montana, which gets 1.4 times the number of representatives it deserves, but Delaware is a loser with only 77% of the representation it should have. Under the Wyoming system the big winner will be South Dakota (1.3 times) while the big loser will be North Dakota (74%).
In terms of over and under representation there isn’t too many problems with the house Represenatives. Yes, Wyoming gets upped to the one representative hard floor, but even without a floor it would still get its one representative due to rounding.
The real issue is in the senate where a filibuster can be sustained by senators representing states with a total population less than that of the single state of California.