Electrospun poly-l-lactic acid (PLLA) fiber scaffolds are used to direct axonal extension in neural engineering models. We aimed to improve the efficacy of these fibers in promoting neurite outgrowth by altering surface topography and reducing fiber elastic modulus through the incorporation of a compatibilized blend, poly-l-lactic acid-poly(pentadecalactone) (PLLA–PPDL) into the solution prior to electrospinning. PLLA+PLLA–PPDL fibers had a larger diameter, increased surface nanotopography, and lower glass transition temperature than PLLA fibers but had similar mechanical properties. Increases in neurite outgrowth on PLLA+PLLA–PPDL fibers were observed, potentially due to the significantly increased diameter and surface coverage with nanotopography. Ultimately, these results suggest that greater electrospun fiber diameter and surface topography may contribute to increases in neurite outgrowth.