I'd go for a few more Omegas and a scout or two. Certainly a couple of Hyperions. The Olympus is pretty useful and fairly heavily armed for a Skirmish ship (turreted Missiles and Railguns). Not sure what's in the new boxed set, but a carrier is a must if there isn't one in it. Especially if you intend to play campaigns as they can replace fighters and supply independant wings to task forces if required. The Warlock's a great ship, but you might prefer to use have two Omegas in your fleet instead (if you use in-service dates it doesn't appear until 2261 or so and as a War priority ship it eats up a lot of fleet points but needs smaller ships as initiative sinks to get the best out of it).
You'll need more fighter stands whichever way you go, might want to have an even mix of Auroras and Thunderbolts if you want a "general-purpose" fleet (Auroras as CAP and escort, T-bolts for anti-ship). There's also the Badger which is somewhere between the two in capability but not worth taking exclusively (too slow and ungainly for general use IMO, but I have them on my Hyperions normally as interceptor support and to finish off badly damaged or AF-less ships)