Personally, I'd go to N. Brother and then head for Fort. When you're returning if you still have enough energy then shoot for Coe. If you don't, chances are you'll have to return to get Fort, and you'll be kicking yourself because you have to climb N. Brother to get there! Not that N. Brother doesn't have great views - it does. But ... better to shoot for N. Brother and Fort on one day, and return for Marston, Coe and S. Brother on another if needed.
As for best route - hmm, only been there about 3 times, and IIRC, always sorta aimed initially for slightly left of Fort's summit. But, it doesn't matter for long as soon you're in the scrub and can only see Fort occasionally. There are a fair number of various paths over there, so I doubt you'll have much trouble so long as you just keep your eyes open.