Ok, moving away from the more famous fighter types.
The RN is probably going to play the major role for the British/Commonwealth forces in the late part of 1945. While the USN would obviously play the central role in Operation Olympic, the RN would have between 6-8 fleet carriers ready for operations (H.M. S Illustrious, Implacable, Victorious, Indefadgable, Indomidable, Formidable) and several CVEs.
As RN carriers don't carry as many aircraft, nor have the long term "on station" capabilities of their USN counterparts, we'll assign them two roles.
First as assault carriers. They get their airgroups in action for one large operation, see a lot of action, and then steam off to rearm-repair-refuel and replace. Sort of a pinch hitter role.
Second role is as support carriers. They piggyback off USN logistics trains (something both navies HATED the RN doing) and operate as rear area security for logistics operations. So, convoy protection, anti-sub warfare and the like.
Apart from the Spitfires I mentoined prviously, the RN flew several other carrier aircraft.
The Mk V Fairey Barracuda would of been the main torpedo bomber for the RN. Operational in late 1945 it was fitted with a 2020 hp Griffon 37, twin .50 cals for defence, a radar pod on the port wing and reinforced structure. It was quite a leap up from the previous Merlin engined marks, but thats really not saying much. It was ungainly, slow (260 mph) and not well liked, but could carry up to 2000lbs of bombs or a single 2700 lb torpedo.
The other Fairey aircraft onboard FAA carriers was the Firefly. It was primarily a long range fighter-bomber and reconnisance aircraftfirst seein s service in action against the Tripitz.. Powerplant was a 1990 hp Griffon XII. Like other Fairey aircraft, it was hampered by unusually thick wings, long fuselage, boxy undernose radiator and reqirement for a 2 man crew. It was slow at just 320 mph max speed, but could carry 2000lbs of bombs or 8 rockets and had good range and a heavy cannon armament. Mostly it would of been used as a dedicated strike platform, hitting costal defences and emplacements under the watchful eye of Seafires.
The Mk IV Firefly was a much improved variant, but it wouldn't of been service until very late 1945. It got an uprated two stage Griffon 74 of 2250 hp, moved the chin radiator to the wingroots and a revised and more aerodynamic nose fairing. Speed went up to about 355 mph, handling and manouverability were also improved.
Much in the same vein as the Firefly was the Blackburn Firebrand.
The Firebrand was originally designed as a naval fighter to specificationN.11/40. Designed as a carrier fighter powered by a Napier Sabre engine it was found that engine unreliability and poor handling made it unacceptable. It was then redesigned to become a fast strike aircraft carrying a large torpedo, and powered by a Bristol Centaurus radial.
Three protypes were built. The first prototype, DD804, was flown on 27 February, 1942 at Leconsfield. It was then sent to A Flight A&AEE, Boscombe Down in April 1942 and undertook its initial service trials in October 1942 at Machrihanish. The Firebrand undertook deck landing trials in February 1943 on HMS Illustrious. Unfortunately, the Firebrand was never much of a carrier aircraft. Its powerful Bristol Centaurus engine and thirteen-foot diameter propeller produced extreme torque swing on takeoff, which could only be countered by the abnormally large vertical tail fin and rudder. The Firebrand was also very difficult to deck land, since the pilot sat closer to the tail than the nose, with predictably poor visibility. While many of its pilots appreciated the fact that the aircraft was built like a battleship, particularly during landing accidents, they did not care for its bulky weight. Finally, the Naval Staff's concept of a torpedo-bomber/fighter combination to which the aircraft was designed was just too much of a compromise, with the end result that the Firebrand was never successful in either role.
Heavily armed and quite fast (355-360 mph with Centarus engine) it would of performed much the same strike type mission as the Firefly, relying on Seafires, Hellcats and Corsairs for protection.