I never coined a weekly mission either and I can do it in 3 or 4 hours with minimal interuptiuons using my specs.
2 fleets of specs:
Cat spec kills the fleet (if somebody hasn't beaten me to it) and the 4 torp towers
Batt siege spec kills the turrets
Both attacks together in most cases take 15 to 20 minutes with zero repair time so i can comfortably do this 3 times in an hour.
This doesn't answer your question though
Marauders, add eng 1, 3 thud 4s and armour to make them 330 or less in total, build yourself 3 or 4 fleets of them and keep spamming them into 25 or lower OPs on auto, they will kill 20s in one go sometimes, anything lower you will auto with them, 25s will work best if you control them but it isn't entirely necessary, this will take you time but if you have time and those tiny little insta repair boats you can do it.
Low to mid level
Preds, you really need to get eng 2 or better on them but once you do use them to kill fleets, keep your little marauders chipping away on auto as much as you can but in between get your sub skills going.
A good tip when using low level subs is to pick the sonar ships and take them out first, in the case of 55 fleets you will notice that one of the dreads appears to have an empty weapon slot at the rear end, if memory serves is is the front right of the rear set, once identified target it because it is the only one that can hurt you while you are submerged.
Do everything as above plus;
Get your wolves building, thud or cut missile will both work with similiar performance, use specials as high as you have (I would recomend waiting until you have level 3 specials but most people cant wait), like what you were doing with your marauders, keep them running out on auto, with level 3 specials it would be rare that any single ship takes more than insta repair damage from a 25.
Mid to high level.
Follow above advice but get your baser working as well, it will be good to rank it anyway, every time its repaired, send your preds to clear the guard from whatever level OP you are comfortable with, generally the lower the level the better the outcome but it will depend on how much time you have too. Use it to the best of your ability and have it repairing between fixing your insta repair fleets and time away from the game.
You dont need any of this advice, go get your points
A couple of final tips;
Dont forget to use your mercenary fleet, they are not good for a great deal of other things so you may as well use them.
Kill fleets first with subs, subs will work on minimal life so even if you do lose them you can have them back on the sea in a matter of minutes and they will greatly reduce your repair time on your main fleets.
Use your bookmarks, bookmark all of the nearby 25s and lower so you can easily and efficiently spam your low end auto fleets
If you know a low level player (around the 20 mark) consider moving near them for a while, if they are where they spawned chances are they will have a lot of low level targets near them and it will greatly increase you points per hour ratio.
Finally, if you know a helpful high level they may be willing to give you a boost by providing you with a shield, have them go in before you with their nice big and powerful (or more to the point well armoured)ship and stay behind them, thud wolves in particular are great for this, especially if they have level 3 specials.
A very good plan if you have a nearby helpful high ender with specs.
Use your preds to kill the guard, then spam torp towers with insta marauders, its going to take a few goes but you will get them, once you do have a high ender drive their bat spec in (yes, just 1) from one of the corners,(bat3, eng3 and a single havoc 1 works great for this) follow them in at the exact same angle about 7 seconds after (exact timing will depend on fleet speed) as they get near the turrets they will start firing at the spec, they will not hurt it while submerged so here is your chance, keep further behind than the spec and as soon as you get in range start turning around ready to make your escape.
If you have thud, AL3, Eng3 and HB3 you will kill a 55 turret in a single run allowing both you and the spec time to get away, with timing and practice you can even get 2 turrets per run and neither you nor the spec driver need take any damage