Most of the metamaterial designs are based on the resonant response of either high-permittivity or metallic particles embedded in a dielectric host (e.g. array of metallic particles standing in air). As a consequence, the response of the material is typically narrowband, and this holds back many interesting applications. Here, we show that the key to achieve a broadband isotropic response may lie on a low-permittivity host with a plasmonic-type response. In particular, we demonstrate that a host medium with such characteristics may enable an effective permittivity and permeability simultaneously negative in a frequency range that may be quite broad as compared to typical designs based on metallic particles standing in a dielectric host. It is shown that the proposed configuration is largely insensitive to disorder and that a slab of the metamaterial may mimic to some extent the Veselago-Pendry’s superlens, enabling negative refraction and imaging with super-resolution.