It sounds like a lot of fun, but unless you set the missions close to the harbors, it will take days. Better off setting it as a MP mission that starts in a certain area and has events in that area occur. Then take the results of that tour and make a new MP mission for another zone and just toss all the participating subs there. You can still split up the sub groups by sending different MP missions to each group saying that they're patrolling different areas and then maybe bring them all together again for other missions depending on events that occured.
I'd be interested, but there's no way I could do a drive all the way from port to the mission areas in 1x, do my searches in 1x, and then return home 1x. My wife would kill me if I left the computer on and had to wake up and jump out of bed when I hear my computer speakers shout "ALAAAAAAAAAAARM !!!!" several times a night.
