Given a quasisymmetric homeomorphism ϕ of the circle, Bonsante and Schlenker proved the existence and uniqueness of the minimal Lagrangian extension fϕ : H 2 → H 2 to the hyperbolic plane. By previous work of the author, its maximal dilatation satisfies log K(fϕ) ≤ C||ϕ||cr, where ||ϕ||cr denotes the cross-ratio norm. We give constraints on the value of an optimal such constant C, and discuss possible lower inequalities, by studying two one-parameter families of minimal Lagrangian extensions in terms of maximal dilatation and cross-ratio norm.