https://imgur.com/a/IS3Os

Large scale Operations conducted by the UNSC against the Covenant and their colonies. Due to being on the defensive, the UNSC adopted a literal ring of defenses. Mostly made up of ODP's, these planets had upwards of 100 Sabre Hangars and between 300-4000 Orbital Defence Platforms. The UNSC fleets stationed at each planet would be significant too. Whilst the command and control vessel of the picket fleet could be any light ship class (Frigates), they provide the first wall of rocks to break the wave of fighters and strike bombers from reaching the Orbital Defence Ring and are usually situated by the Slip Lanes.

@sloosecannon Thanks for fixing my from before, I'll delete the original post and do it properly this time. Thanks again, though. :)

So I start a new game and the gravity well, grid and slipspace lanes no longer appear. I have toggled cinematic on/off and even deleted the game and re-installed it. Still, doesn't fix it. I am not really sure what caused it since it just appeared (Well, disappeared) out of the blue.

UNSC: Build Orion Carriers and a couple Marathons to escort alongside no more than 10-20 Paris per fleet as a basic composition.
Research the Destroyers for Anti-Ship and Stalwarts for Anti-Air for later fleets to replace the Paris.

Use the Orions to colonise planets whilst the escorts attack the pirates and whatever else is out there. Having a large number of Stalwarts can allow you to build carriers that solely have bombers, as they will help finish off the ships hit by MAC rounds and draw the attention of the enemy fleet and accompanying fighters. This will also expose the enemy bombers making a run for the fleet allowing the AAA to take them out quickly.

Keep the number of Sloops roaming up, send them out in pairs in case one is destroyed. You can use the Heavy Prowlers, but they need constant attention, as they don't have the "Explore" ability. Leaving mines in each system allow you to monitor the system.

Only build the Infinity if you have an enormous excess of resources. Smaller ships can get the job done.

That and you need a certain Spartan's Luck if you're fighting the Covenant.