An idea. I save the picture bellow, of an US Navy concept of an large USV, so I went "hmm" what about an frigate?:
Note the drawing is in an overloaded configuration, and aren't reflecting the loadout it would have in the real world, but is just an illustration on what various things that can be fitted.
- a large launch deck aft for larger vessel, with a sort of crane/slip system for launch and retrieval of vessel.
- Side hatches for RHIB and USV/UUV
- Abnormal helicopter deck, for medium helicopter and UAV. With space for a "possible" catapult for winged-UAV.
- Center weapon deck with VLS and NSM (with surface and land attack capability)
- Forward deck with either 76 or 56mm cannon
- aft weapon deck with 40mm cannon or RAM
- Various self-defense systems
- Phased panels for: 3D radar, communication, illumination, electronic warfare, satellite communication, drone control, electronic detection, jamming, etc.
- a light to medium set of "conventional radars and electronics" to back up ships main radar and electronics
- towed sonar, the launch deck is capable to house containers with CAPTAS towed sonar, sacrificing space for large USV
- Bow sonar + additional underwater sensor further aft on the hull.