Hello Brian -- Welcome to the Forums!
Depending on year, a somewhat lighter 25' Airstream can be towed by the most capable 1/2-ton rated tow vehicles (eg, GM or Chev 1500-HD). There are a number of choices -- Suburbans, certain Toyota Tundra models. You most definitely want an 8-cylinder with an axle ratio of 3.73; 4.1 is better if your tow vehicle is undersized.
I took a look at the Ford Freestar on the internet. It can be equipped with a Class II hitch at the most and even then is rated for 3500# tow capacity. It's also a 6-cylinder with an axle ratio of 3.54 if I recall correctly. My '74 Argosy is about as light as a 24-footer can get -- and it's 3900# empty
. Honda Pilot won't fare any better.
It gets hard to have an economical family hauler become a big hungry tow vehicle on weekends. I think we can find some choices that aren't in the full 3/4-ton range if we have a chance to talk it over. Best wishes!