Long SubA-SubB.Domain.com Issue

[mikestuart]

I have www.domain.com (PR4) and 5 other related sites as SubA-SubB.Domain.com (PR3)
Where SubA-SubB are city names, so it looks like NorthMiami-FortLauderdale.Domain.com
and www.domain.com is Miami

The URLs are very long, but they do show up on 1st page Google for best keywords

Which is the best option to create shorter URLs

1. 1. Create shorter URLs that forward to long ones for customers and Print Ads
2. 2. Change to Domain.com/SubA and Domain.com/SubB and 301 to them
3. 3. Change to DomaninSubA.com and DomainSubB.com and 301 to them
4. 4. Split to shorter Sub-domain URLs by at least removing the dash: SubA.Domain.com and SubB.Domain.com and 301 to them
5. 5. Don’t change anything