No, they aren't, not in the full meaning of the word.
That scan you provided says the Uzumaki are distant relatives of the Senju, not Senju themselves. Add to that the fact that Naruto is only half Uzumaki. Now top it all off with the fact that Naruto was only named "Uzumaki" so that it wouldn't be known he's the son of Minato Namikaze. You've basically got the farthest thing from a Senju you could get, right after non-Senjus.
Counting Naruto towards the Senjus is pretty much clutching at straws, how does a completely separate clan equal Senju, anyway? Nagato, Karin and Kushina are whatever, anyway. They're good shinobi, but nowhere near the level of Uchihas.
Hashirama is indeed the pinnacle of the Senju, but he's still easily in Top 10, so does it matter?