Hi BGray
I'm glad you feel so inspired by all the holidays available. It really is a difficult choice, isn't it?
On the stopovers, you generally won't have a tour manager with you but you will be in places that are very easy to get around. I've been to Hong Kong, Singapore and Bangkok and found them all very friendly. Hong Kong in particular has a great subway that will take you where you want to go, and in both Hong Kong and Singapore, English is spoken widely.
http://www.justyou.co.uk/destinations/europe/eastern-europe/croatia/
We also do a very good rail tour of eastern Europe, visiting four amazing countries:
http://www.justyou.co.uk/destinations/europe/grand-rail-journey-through-eastern-europe/
And although we don't have a Baltic tour, we have just introduced in tour of Krakow and Southern Poland, which isn't far away.
http://www.justyou.co.uk/destinations/europe/eastern-europe/poland/krakow-and-southern-poland/
As far as I know, there are no plans for a Route 66 trip at the moment but I will pass your suggestion on.
Let me know if you need more advice about any of these tours.
Kind regards,
Olly, your editor