κατάρχεις: pres., because the sense is you are (still) the leader.
The apod. of εἰ εἴποι, naturally expected after ὥσπερ (i.e. ἂν γένοιτο), is lost sight of, and instead of it, καὶ ἐγὼ τοιοῦτόν τι ποθῶ follows with anacoluthon.
τὰς . . . ἄκρας: the hands. Homer often uses χείρ to denote the arm.