LandSharkUK has a fun program where you take some entering arguments about what some version of the planned Royal Navy Type-31 frigate may or may not have on it. The template is the proposed BMT VENATOR-110 Frigate.
You can pick any mix from sensors, to weapons, to engineering, to aviation/mission support.
I made a few compromises (always get the largest gun option, natch) - and here is what I came up with in about 2-minutes of pondering. I'll convert to Imperial and USD for you;
SALAMANDER Class Frigate
Length; 463 ft
Beam; 58 ft
Draught; 16 ft
Displacement; 4,821 tonnesAnd yes, the pic is about my ship ... with frick'n lasers instead of CIWS.
Top speed; 33 Knots
Range; 7,231 Nm
Armaments and sensors; 5" main gun, 24 CAMM & 8 MK-41 VLS Cells, 2 Phalanx CIWS, decoys and ECM amidships, CAPTAS II Sonar.
Aviation support and mission bays: average range.
Engineering; two diesels and a gas turbine (CODAG).
Unit cost; $519 million
Royal Navy Budget for T31; $3.12 billion
Units possible from budget; 6 Units
UPDATE: If you are wondering what this STRALES system is, go to the 2:50 point in the below video.