Op, if you are still struggling or if anyone else is, I have lots of success against the redacted with this fleet composition. Try it if you can in your current playthrough or in a new one.
Its an all low tech fleet that's useful for all stages of early to mid to late game and obtaining the ships are easier to get early. However I use (XIV) Battlegroup versions of these ships which are slightly harder to obtain early but I've seen the enforce and dominator (XIV) versions in hegemony worlds black markets but the regular versions work as well if less effectively . Might have to sacrifice points in vents or Caps to close the gap compared to the (XIV) versions. You'll also have to invest into certain skills for officers and your own skill tree.
Required skills for your character are: Coordinated maneuvers, Crew Training, Officer Training, Electronic Warfare, Flux Regulation, Special Modifications. You'll also need in total 45 story points in order to have all necessary hull mods.
Although not required for your own character these combat skills will really turn you into a killing machine as well as your officers but are a must for your officers: Helmsmanship, Target Analysis, Impact Mitigation, Shield modulation, Gunnery Implants, Reliability Engineering. For your officers, Elite skill Shield Modulation first, Target Analysis second or if you prefer helmsmanship instead for more consistent speed. Mentor your officers for aggressive.
This fleet will have 15 ships on the field in total with reinforcements of 2 dominators(XIV) and 3 lashers(LP). Have your 8 officers pilot the destroyers and hire 2 mercenary officers for the 2 heavy cruisers and if possible find them with at least Shield modulation as an elite skill however finding them with at least the same skills as your officers are good enough. 4 Lashers, 8 Enforcers, 2 Dominators, 1 Onslaught which comes up to 178 combat deployment. 240 Max with the Reinforcements.
These ship builds were made during 0.95a RC15 update.
Lasher (LP) Class Frigate. Design type Luddic Path.
2x small Light needlers, 3x small Light mortar. Built in Hull mods: Hardened Shields, Hardened Subsystems, Flux Distributor. Regular Hull mods: Solar Shielding. 10 Cap, 20 Vents.
Enforcer (XIV) Class Destroyer. Design type: (XIV) Battlegroup.
2x Medium Heavy Mortar, 1x Medium Heavy Needler, 2x Medium Heavy Machine Guns. Built in Hull mods: Hardened shields, Hardened Subsystems, Unstable injector. Regular Hull mods: Safety Overrides, Solar Shielding. 0 Cap, 30 Vents.
Dominator (XIV) Class Heavy Cruiser. Design type: (XIV) Battlegroup.
1x Large Storm Needler, 1x Large Hellbore Cannon, 2x Medium Duel Flak Cannon, 7x Small Vulcan Cannon. Built in Hull mods: Hardened Shields, Heavy Armor, Integrated Targeting Unit. Regular Hull mods: Resistant Flux Conduits, Solar Shielding, Stabilized Shields, Flux Distributor, Armored Weapon mounts. 16 Caps, 40 Vents.
Onslaught (XIV) Class Battleship. Design type: (XIV) Battlegroup.
2 already built in Thermal Pulse Cannon, 1X Large Storm Needler, 5x Medium Heavy Maulers, 4x Medium Sabot SRM Pod, 8x Small Vulcan Cannon. Built in hull mods: Augmented Drive Field, Heavy Armor, Hardened Shields. Regular mods: Expanded Missile Racks, Integrated Targeting Unit, Resistant Flux Conduits, Solar Shielding, Stabilized shields, Flux Distributor, Armored Weapon Mounts. 25 Caps, 60 Vents.
Consider that every ship here can take on the same class of ships with ease or below but when piloted by officers the ships can punch above its class by 1. However when fighting against Redacted avoid having your frigates or destroyers fighting the Radiant ship when its supported as they will be destroyed if caution isn't taken around it. 3 destroyers piloted by officers can keep a Radiant suppressed and eventually destroyed assuming its not supported. Ensure the cruisers or the Onslaught engage the Radiant ship first.