I also have a high instep and also tendons with fluid around them (ganglions).

It varies from day to day. It is also worse with fluid retention.

Just so you know it has gone down remarkably since I started the r-lipoic acid.
So has my edema.

But I have to be careful of too tightly tied shoes, shoes or boots that hit that area, and I have to have a very soft padded tongue in any tie shoes. (or my feet will go numb)

I just bought a pair of Crocs at Costco and am very happy with them (the real Crocs and not a knockoff). The plastic stretches over the instep and does not compress anything. Many slip on type shoes/sandals hit me wrong).
The first week, the little bumps on the inside bothered me, but now I am used to them.
There is alot of cushioning in the sole, so my heel spur and sesamoids are happy too.

I think I will switch now to Crocs...the slip ons I had were compressing the ball of the foot and I'd have pain at night.