Could cruise be modified, so that if we "cruise 2 *n" from inside of a
harbour, it acts like "sail 2 n" instead of giving a "can't cruise indoors"
message? right now to get from 1 harbour to another I have to sail 2 n,
trigger the 'done sailing', and cruise into the next harbour + anchor.. would
be nice if cruise 2 n,...,...,*anchor could take you from one to the next?

While this would definitely be a nice feature, and one i've requested before,
this shouldn't be a problem for most ships (any air capability), except at
laenor ferry which bugs lamely. Most harbors, you can fly over the harbor, and
'ship secure' and land inside. when you next 'ship launch', you'll be above
the harbor and able to cruise immediately.