We construct a sequence of primitive-stable representations of free groups into whose ranks go to infinity, but whose images are discrete with quotient manifolds that converge geometrically to a knot complement. In particular this implies that the rank and geometry of the image of a primitive-stable representation imposes no constraint on the rank of the domain.
"Discrete primitive-stable representations with large rank surplus." Geom. Topol. 17 (4) 2223 - 2261, 2013. https://doi.org/10.2140/gt.2013.17.2223