Certain techs, as well as certain improvements (Arcean nav center in TA, hyperion shipyard, gravity accelerators trade good) give a +1 passive bonus to speed. In TA, the base speed is raised to 2 as well. Furthermore, +1 speed only costs 5 points, and the only race that only has 7 points to spend is the DL/DA Torians. Last I checked, the TA Torians were updated to 8 points, and the Thalans have always been 8 points. Custom race, which is generally regarded as the best or one of the best options, nets you 15 points.
So which game chapter are you playing, exactly? And version, for that matter?
Your flagship can auto-survey outside of the range that you can manually send it, although it's not always reliable. Range is a funny issue, though, and even in a gigantic or immense if you get a foothold on a planet close enough to your opponent, you don't need any range modules.
Additionally, which AIs are you playing against? Several AIs in TA have an inherent +1 passive bonus to speed-among them the Terrans, Drengin, and Altarians. Are you noticing the speed discrepancy with all races, or just them?