A corner base design is very common in the early stages of the game, and it is often effective since it reduces your optimal attack surface. A few comments at first glance:
1. Put a buffer of other buildings between you HQ and the edge of the map. Your opponents can still deploy from ALL edges of the map and with your HQ so close to the edge with no walls or other buildings to obstruct fire, it's a very easy 1 star win for the attacker. TIP: put your resource generator buildings and barracks along the back corner as a buffer for the HQ. You can also consider putting some walls back there if you want.
2. The strength in a corner design is that when the opponent deploys on the edge in the corner, those units are instantly vulnerable to defensive fire and they are at basically zero range to the buildings...however to take advantage of this strength, you need to put some turrets close enough to the back corner that they will target any troops deployed there. TIP: Move some turrets back closer to the corner.
Other than that, I'd recommend you watch your defensive replays and try to adjust your base design progressively as you see what strategies the Imperial's commonly use against you.
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