I agree with you that they don't read very well... at this size you should be bold and attempt some strong hue-shifts and try to up the contrast significantly. It's usually better to keep checking out if it reads well at 1x zoom, usually if it does at this size then you're in the clear at other sizes.
Also, i'd attempt some redesign on some of them, i can't quite tell what some are. Make it painfully clear :)
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