Hmm, I'm still playing, and I feel like you haven't need to do a big circle.
I tend to try to create a small circle of like ~14 tiles without forcing it. That mean I try at the same time to resolved the exits on the outside.
Since I don't care how much exit I have in the middle, it let me put some tiles which are usually bad, but are fine here to create the circle.
And it's like 2games in one. The outside, and the middle. But since I used many hard tiles to do the circle, I usually can close the outside at one moment.
I tend to try to create a small circle of like ~14 tiles without forcing it. That mean I try at the same time to resolved the exits on the outside.
Since I don't care how much exit I have in the middle, it let me put some tiles which are usually bad, but are fine here to create the circle.
And it's like 2games in one. The outside, and the middle. But since I used many hard tiles to do the circle, I usually can close the outside at one moment.