Toe overlap is not really that big of a deal. You never notice it unless you are going really really slow... and who goes slow on a track bike? I only notice toe overlap when coming out of a track stand. You never do a 90 degree turn in the streets where the toe overlap would be an issue.

there are an abundance of track frames in smaller sizes. it is actually harder to get them for taller people that are 6" plus. Look at Japanese frames. Track racing is huge in Japan and all the frames are for small riders. Check ebay or craigs list if you don't believe me and you will see that most of the frames are 53 to 55cm.

Track frames look great when they are smaller sizes - it is one of the only advantages of being shorter.