Things need space. You are trying to place all end game material in a fairly small area. It is possible but you have to build inside the constraints you have put on your self. The game doesn't expect you to cheese it and make big islands.

Nor does the game assume you are going to try to build a full end game base like that in a 26x26m-28x28m area. My starter base I felt was compact and it was 28x28 inside (room for 196 floor tiles) with walls defenses that were/are 8m thick. Inside the 14 I had everything really needed up to Moder. (Small Garden, Boar Pen, Work Bench, Sleeping/Rest area, cooking, Smelter x2 Kiln, Bee Hives, storage, and upgrades. Other than being larger than what you suggest it meets all the requirements. All you have to do is place the fire on one side and the boars on the other.

The fire isn't an issue it is you are trying to do something that it wasn't designed for. (Not a criticism... but it is a reality and that means you may not always succeed or have to get creative) Fire just has to be 6 floor tiles (maybe closer) away.