Assistance needed with making the most out of a wine kit.

A friend and i plan on making a few red kits and blending them before bottling. We want to make the best possible wine. What are some tips to make the most out of a kit? Adding more sulfites to age longer? use different yeasts? leave it on the lees longer? I plan on using the eclipse wine expert kits. Any other kit recommendations? I want to age the wine for a few years and make something that will really improve over time.