Yes, I will redesign my board with a few optimizations and 2 caps by MAX7219.
I've just measured the breadboard prototype, it draws between 130 and 150 mA. I find it to be quite low, but it's a realistic model since it has all the parts in need (including caps :)).
I think a standard USB port can handle up to 500mA so I should be fine.
Cheers,
Fred