Reducing this town's cost(??)

[ReluctantSamurai]

The Senate hasn't help by asking me to capture towns miles from my front lines which are then retaken or continually harrassed

As stated earlier, you can ignore some Senate missions...just make sure you complete enough of them to keep from getting docked money

The Gauls have been a real pain in the butt and really slowed my progress by attacking and regaining settlements I had just taken

The Julii were my least favorite Roman faction so I never played them much but a few things I learned... Once you capture Patavium and Mediolanium, there are three mountain passes where you can build forts that essentially stop them cold. The first is to the west of Mediolanium and it forces a river crossing to boot...easy to defend. This will force the AI to try the pass just to the NW of Mediolanium where you can build a fort. More difficult defense than the first, but still to your advantage. The third is to the NE of Patavium. Another narrow pass where you can build a fort if needs be. You can defend all three without a fort if you wish. In every case (and this isn't always the case when defending mountain passes...discussion for another time) you will have a decided terrain advantage and should crush any attempt by the Gauls to retake. These are the only three ways a Gallic army can reach those cities other than a looong circuitous route through Dacian territory. This will buy time to consolidate before beginning your "Caesar in Gaul" campaign. Or maybe you'll want to head off to Greece for richer lands and just hold the Gauls at bay There are plenty of Julii campaign suggestions in the RTW guides forum, and it might be helpful to browse a few....