Some ideas:
Put barracks and stables behind TC with gather point just in front, so raiding and rushing armies come under TC fire before they burn down your military buildings.
Put the first tower or two just forward of your TC or if you're building a forward base, just in front and lateral to your military buildings. This way it won't alert enemy units to its presence unless they are attacking it, in which case they come under tower fire.
If your secondary hunts and mines are a ways from your base, put a tower just behind them so gatherers can retreat into the tower and buy you time to respond.
When building walls, if you only have a few wood to spare and don't want to waste villger seconds, build your first walls as a screen to delay enemy getting into your eco. even if you only build 3 or 4 wall segments, build them in such a way that they shield your flank and direct enemy units to go around them via towers, TC fire, and military gather points. later, you can expand the wall as needed. A good arrangement is to have a partial wall running along inside your TC fire range (just inside of it so attacking units get into its range) between 1 TC and 1 tower. In the middle between the two is your military gather point for ranged infantry, sort of like a box. Raiders and rushers have to send their melee troops around the sides of the box, getting TC fire and infantry volley. Meanwhile your eco is safely garrisoned for now.
Use nearby cliffs and water as a natural barrier. If your starting tc is close to water, build a dock to help defend your flank with ships. Likewise your tc fire will help cover and defend your docks and any fishing you do. If your starting TC is close to a cliff, use walls and towers to make attackers have to navigate around the cliffs and soak up a lot of tower fire.
Probably the best advice is to be aggressive. Applying consistent pressure on their own base will keep them out of yours.
Crunkatog on ESO
Bart331 balance suggestion: aztec: remove civ
Voltiguer: Ender, Sioux in 1.04 will be a top civ, no matter how many layers of Sioux goggles you put on
schildpad on Elephants: ...their mansabdar unit sucks so hard it looks like a black hole
Crunkatog on Steam.