DIY - school shoes for sensitive feet

Has anybody found it difficult to find plain black school shoes, textile and pretty open not to overheat small feet over summer? As for me I could not find a proper pair. There are lots of shoes but mostly they are made of thick and stiff leather. For sensitive or sore skin it can be a real trouble.

I failed to find soft textile shoes, plain black, with flexible sole,  size 11 (for some reason they start from size 12 or 13), so I did them myself.

I took these Emerson shoes you can find in every Target or BigW for $5 (sometimes even $3.5 on sale).  They are very soft, and sole is flexible, which is good. But they are really hard for five-year-old to put on due to wide elastic inserts.

Shoes as they were when I bought them. 

 First of all I took off the elastic inserts.

Insole is black and green on some photos - because I made two pairs of shoes, one with green and one with black insoles.  Some photos are of one pair, some of another.