The Ranger was the USN's first purpose-built carrier, where Langley, Lexington and Saratoga were conversions.
She was modern in comparison to others, as she was from the mid-30's and the reason she was kept in the Atlantic, was because of her speed (less than 30 knots), not because of her abilities.
Matter of fact, the Ranger tried to lure the Tirpitz out of hiding, which didn't happen, unfortunately.
In Nov 1942 FDR asked Churchill for assistance in the south Pacific in view of the loss of Wasp, Hornet & the damage to Enterprise, so leaving Saratoga as the only fully operational carrier. On 2 Dec 1942 Churchill replied offering both Illustrious (then in the Indian Ocean) and Victorious (detached to Force H from the Home Fleet) if Ranger could be sent to join the Home Fleet. FDR responded as follows (with my emphasis):-
"[PREM 3/163/1] 5 December 1942
Carrier reinforcements for South West Pacific
Your Despatch No. 217 of December 2, 1942, has received serious consideration. Your offers of co-operation are deeply appreciated. In spite of the advantages which would result from the employment of both VICTORIOUS and ILLUSTRIOUS as a tactical unit in the Pacific other considerations make it necessary to forego the services of VICTORIOUS there. If it becomes necessary to send yet another carrier to the Pacific in the near future, RANGER would be chosen because she does not require special preparation for operations with other American forces. The early arrival of ILLUSTRIOUS in Pearl Harbor is looked forward to with anticipation."
The RN subsequently decided to send Victorious (she left the UK on 20 Dec 1942), while bringing Illustrious home for a refit in Jan 1943.
Ranger's design speed was 29.25 knots, and she must have been able to run close to that in 1942. There were plans formulated in Jan & Dec 1943 to modernise her which would have included blistering her hull, which would have reduced her speed. After that her speed was expected to be 28 knots. Instead she was given a much more limited modernisation in early 1944 for use as a training carrier as she would have caused delays to the completion of the Essex class Shangri-La and Lake Champlain at the Norfolk Navy Yard.
Victorious' design speed was 30 knots, just 0.75 knots faster than Ranger. That seems to me just not enough to make a difference.
Wasp' design speed was 29.5 knots.
As noted in earlier threads, the general carrier group operating speeds were in the 15-25 knot range, so while her speed was lower than the Lexingtons and subsequent Yorktowns, I do question just how much of a limiting factor that alone was. Perhaps more importantly, Friedman also notes
".....she could not operate in common Pacific swells nearly as comfortably as could the larger ships." So it was perhaps the combination of factors that made her unsuitable. Between 1935 & 1939 she had been operated in the Pacific so the USN would have been fully aware of her limitations.
Ranger was sent to join the Home Fleet in Aug 1943 to release Illustrious to go to the Med to join Force H as a replacement for the torpedoed Indomitable. But I fear you may be confusing the operations she participated in.
8 Sept 1943 she sortied from Scapa with the Home Fleet in a vain attempt to intercept Tirpitz, Scharnhorst & the 9 destroyers that carried out Operation Zitronella against Allied facilities on Spitzbergen. The KM were back in port long before the Home Fleet got anywhere close.
On 2 Oct 1943 she again sortied with the Home Fleet. The purpose of this Operation, Operation Leader, which took place on 4 October 1943 was to strike shipping in the Bodo area, 370 miles south of Tirpitz lair in Kaa Fjord. Add to that Tirpitz had been badly damaged on 22 Sept during Operation Source by the X class midget subs so was going nowhere. The suggestion in some US newspapers that Tirpitz was hiding from Ranger & her air group was a bit of Allied morale boosting propaganda. As shown here
Air Group 4 During World War II - Casablanca to Tokyo
airgroup4.com
She remained with the Home Fleet until late Nov 1943.
Operation Leader was a follow up to Operation Camera in July 1943, when the Home Fleet simulated an assault on southern Norway as a diversion from what was happening in the Med. All part of a plan to tie down German forces in Norway.