When I suggested the WM20 egg, I meant to
replace the SPG-53 forward. It can handle 5/54 gunlaying.
I think you'll agree that this substantially improves the arrangement
Ah. This would solve many issues with aesthetics, although I disagree that it improves the vessel. The lack of a very visible, dish-like gun fire control radar detracts to the charm and anachronistic feel of the ship overall.
I want to point out that the Brooke class frigates were a compromised design (which is true of all ships in some manner) on the basis of cost. As a convoy/open ocean escort, they provided limited ASW and AAW capabilities (but still far more than a lone merchant ship with nothing at all) and were meant to operate in concert with other armed vessels, whether other Brookes (or Garcia class ships, or what have you) or more capable vessels like say a SpruCan or a Leahy. Also, the Brookes originally had a very short helicopter hangar (for DASH drones) so the original firing arc of the Mk 22 wasn't impeded until they upgraded to LAMPS. I'd rather have the missile launchers be less impeded than the gun, or take the gun out if you have to (like acelancelot said).
So the main thing you have to ask yourself is, what is the primary mission of this vessel? If it's to act as an ocean escort, then your standards of "good enough" will be lowered that much further. If it's going to be the primary AAW/ASW asset of your navy, then you probably won't want to compromise as much - then again, maybe you don't have much choice given the navy's budget. In which case you really better pay attention to what you want to prioritize.
It's supposed to act as a light, general purpose escort for keeping Megaconvoys of Detroit steel MBT-70s from being sunk by all the Akulas in the USSR. It's also supposed to work with British Type 82s and CVA-01 Invincibles to keep the Northern Sea free of Evil Commies like Delta IV and Project 748 assault submarines. In this regard it's about as well equipped as contemporary USN frigates to do this job (Garcia, Brooke, Knox, sea trial Perries).
It would probably also perform admirably in keeping the Soviet floating fish factories from stealing all of Gallia's cod. But cod is a secondary mission to keeping the Megaconvoys protected with other NATO light vessels and acting as ASW support for Allied carrier battlegroups.
I'm not sure where you're getting the idea that thing is going to operate alone, it lacks the air direction capability and datalinking necessary for independent operations. It would probably end up being supported by a Leahy or something that would act as a nerve center for air defence of the convoy, and the destroyers would be the ASW defence/cheap ships intended to eat Type 53-65 wake homing torpedoes so cruisers and CVAs don't.
Yes, these are cheap ships intended to be produced and operated within the greater fleet of the Allied navies. I'm not sure why they'd be anything else for a stereotypical Western European country, or where you got the idea that they were necessarily intended to operate alone by themselves.
The North Atlantic is not very big, I'm sure if The Final War happened in 1982 or so when all these things finished delivering, then they would necessarily be attached to American convoys and put under the command of American cruisers and destroyers, which are far larger and better equipped at handling duties such as command and control. Yes, this isn't a command ship, it's a ship that's intended to be part of a larger force, like all ships, and necessarily compromises in certain aspects such as protection. For example, the entire superstructure of aluminium. It's not intended to be a Spruance, or a Leahy, or other ships two or three times its tonnage. It's supposed to work with these ships instead, not replace them.
More importantly, this isn't a Brooke. It's not even designed by the same people, they didn't even look at a Brooke when making this ship, it just sort of happened to be a case of convergent evolution.
She's not intended to punch above her weight or anything, it's just a thing so Gallia can have a indigenous blue water force that isn't USN stock Leahys, Belknaps, Kitty Hawks, and Forrestals.