Ok so I'm gonna divide this into 2 sections, essential fixes & optional.

I was having no end of grief with this game, more so on the racer side than cop side of the game, flickering textures, bad pop in, disappearing roads leading to soft lock crashes requiring the process to be terminated in task manager.

I assume you're running windows 10 & a pc that isn't a potato going by the games recommended requirements, for reference I have an I6700k, gtx1070 & 32gb ram, SSD, nothing special by 2021 but more than enough for this game all maxed.

I used https://www.pcgamingwiki.com/wiki/Need_for_Speed_Rivals as a point of reference before starting the game so check that for a few things.

I had in game graphics set to the highest option yet some values still were not set to the highest number of 3, these will be mentioned later.

The Abyss or disappearing roads leading to everything being static & soft lock crashed - For this issue go here C:\Users\YOURUSERACCOUNT\Documents\Ghost Games\Need for Speed(TM) Rivals\settings or whatever drive letter your my documents is in, open PROFILEOPTIONS_profile with a text editor (I use notepad++) & look for GstRender.MeshQuality

Mine was set to 1 & the cause of the textures not loading in & most problems, change that to 3; save the file.

Weird flickering pattern & odd lighting - There are 2 .exes, NFS14.exe & NFS14_x86.exe, I renamed the first one to something else & renamed the second one to NFS14.exe then used that one, flickering gone.

Want more than 30 frames? Of course you do, according to the link above there are issues with certain things due to the timings being off so just be aware of that but give this a shot anyway. In steam go to your game & right click then properties & under launch options enter -GameTime.MaxSimFps 60 -GameTime.ForceSimRate 60.0 -Render.ResolutionScale 1.5

That last thing will make the game look a bit nicer.

making it look better - Again in the PROFILEOPTIONS_profile make sure you have this:

GstRender.AmbientOcclusion 2
GstRender.EffectsQuality 3
GstRender.HeadlightShadowsEnabled 1
GstRender.MeshQuality 3
GstRender.MotionBlurEnabled 0
GstRender.ReflectionQuality 3
GstRender.ShadowQuality 3
GstRender.TerrainQuality 3
GstRender.TextureQuality 3
GstRender.UndergrowthQuality 3

Not sure if there's a 3 for the first thing or you even want it but make sure the ones with 3 are at 3 & not 1, save.

A mod for more cars on the racer side (set game to single player if doing this, it's not online friendly), instructions in link.
https://nfsmods.xyz/mod/1182

Get rid of microstutter/jitter: (only if you know what you're doing)
Download RTSS standalone https://www.guru3d.com/files-details/rtss-rivatuner-statistics-server-download.html, once you have that up & running add the game exe & set fps to 59 if you're using 60, show own stats = on, this is more for ppl that are familiar with this; if you're unsure leave this as you may mess something up. For reference I have a g-sync monitor & set global to 3 frames less than the refresh rate I'm running. If you're using v-sync or something you'll get different results.

A few other things that may or may have no impact:
Go to game exe & right click, properties, compatibility & run for windows 7 & tick disable full-screen optimisations.

Grab https://www.wagnardsoft.com/ISLCw & have that running, will flush out ram if it starts getting low. (read instructions on forum)

If you're using a controller & have the steam controller configuration enabled, right click the game, properties then controller tab & make sure you have it set to disable steam input to avoid any potential double input issues, this is important if running a game with in-game controller support being plenty sufficient.

That about covers it, hopefully you're issue free now.

It seems to me there's a theme of games ported from console to pc that happened to be on 2 different generation consoles at the same time in that sweet spot between transitions having issues out the gate, I reckon it's due to too many variations going on between them due to hardware limitations of the older gen hampering the optimisation for newer tech thus certain settings that should be on for newer hardware are set to the lower "safe" values.

If you're still here; may as well watch a video, have a good time - https://www.youtube.com/watch?v=ZlY5PQkNp7g&t=5s