I think everyone but Babcock is missing the most important point here. Normally I would help OP along, but I think he is gone since his report is due, and maybe this will help people googling in the future.
. The answer to how to improve yield of a Fischer esterification is to find a way to remove water from the reaction. Whether that be by azrotropic distillation with Dean Stark or the addition of a drying agent, this is the single most important factor to get Fischer to work.