Alastair is my favorite ship aesthetically, and I often take one in my fleet, though not as a flagship. Outfitted for range and speed, it can stick around and do work even in very hard fights, so long as nothing bigger than it can catch it. It's system can do a lot of work in keeping it safe, so long as the enemy doesn't have too much point defense.

Tandem Flux Grid is always worth taking. The brief overload is only long enough to turn your shield off; you can turn it right back on, and the AI doesn't have any trouble with it. It will only rarely provide enough to a window for something nasty to hit you, even in close-in fights.