It’s hard to put them on the same spectrum but I would say yes he is. Mostly, he wants Israel to be less apologetic about incorporating Jewish values in its governance. You can find his website at www.jewishisrael.org.
Netanyahu is opposed to this and has shunned Feiglin, including leaving conferences to avoid the possibility that they would have to shake hands.
If the poorer than expect result is because of Netanyahu’s downgrading of Feiglin that is very unfortunate.