don't be ridiculous... look at what a 100000 tons ship would look like :
http://www.kryon.com/cruise%202003/cruise4more.html
I think it's definitively not the size of a scout ship. Moreover, spaceships are built in light materials, so they would be even bigger. Ship tonnages mustnt'be considered as real one in SE IV. they are just a way to say " a light cruiser is two times bigger than a fregate".
That's the way I think when designing shipsets.