Andy said:
The Netherlands part looks doable in about 2 hours
train from Hoek
van Holland - Rotterdam - Eindhoven and £78 return plus £29 each way
for a cabin if going overnight seems pretty cheap.
In terms of sleep etc, you would probably be better off doing the
Eurostar to Belgium and getting the train from there. On the ferry, even
with a cabin, you have the unknown Channel weather plus the hassles of
immigration and customs on arrival.
I once did Rotterdam - London overnight on the basis that I'd be able to
sleep. No, I just ended up needing to sleep through the following day.
The delays at customs in the early hours didn't help.
Ian