Wylde: Holds a major stronghold (Rain House), also is a minor vassal of a Great House.

Vypren: Holds a major city (Fairmarket) due to our canon, also is a minor vassal of a Great House.

About equal if you draw lines in the sand. Looks like House Vypren has been around since before Aegon's Conquest and have some mentions about importance. 

[b]Historical Ancestors:[/b]
[url=http://awoiaf.westeros.org/index.php/Vorian_Vypren]Vorian Vypren[/url]
[url=http://awoiaf.westeros.org/index.php/Jasper_Wylde]Jasper Wylde[/url]