No i don't have this issue, but trust me i had my share of random crashes.. 
But up until now , no crashes anymore.....(but as i progress that might change offcourse)
I too read somewhere, that this change in the xml, can cause crashes, but that will depend on system specs too offcourse.
Hmm, that's strange if it only happens after a while in vanilla game,
Although that might be because of the possible 'corrupt' game folder.
You should reinstall the game again, and try to play a while vanilla, see what's that giving you....
just to be sure that your vanilla game works correct.
If not, then you should monitor your temps, (mainly graphics card) (might be a heat issue then) and maybe reinstall
your graphics driver.....
Also if your vanilla game doesn't work, ....do you have other intensive games that you play? do these cause any type of graphical glitches, not exactly like this one, but something similarly weird ?
@Mackyn1878
Well the good thing is, it's mod related then, did you redownloaded the mods?
(If not, could possible be corrupt files)
Otherwise, possible mod conflict, or outdated mod(s).
And if you try to play without mods now, does it work , or will you need to reinstall again?
If vanilla game isn't working the moment you try it with mods, then would you care to explain how you install mods into your game? because if your game works without mods, after reinstalling gta5 , and you add mods, then you get the glitch,
and if now, you try to play gta5 without mods again, and it's still doing the glitch, then i think you change files in the wrong place or something, don't know......
If (with this glitch you had again) if vanilla game still works correctly,
I suggest you try to enable one mod at the time, to know which one is causing it.
@Morgesan
Normally everything that exists in the game folder, when any file from there, is needed for a mod, the whole archive where the file is in, needs to be copied to the mods folder, (you'll never need to change anything in the .rpf files (archives) in the game folder,....
In short all the archives that wil change because of mods, needs to be fully copied to the mods folder. and from there you mod the files.
As for visuall V , i don't know i don't use that.
But i do know, that if a mod adds archives (in the dlcpacks folder for ex.) then you'll need to check in that archive also, if a file is in the archive from the mod, (dlc.rpf) and that file exists in the original game , then the files in the mod archive will be used instead of the ones in the original .rpf archive.
Easiest way is, just to search for the specific file in openiv but beware though as some files will not show up if searched for.
It depends the file you search is inside an archive in an archive......
@Morgesan
The link to mod is not linking to the mod (which mod did you try)?
Also are you sure you converted the sound files to the correct format?
Most sounds in the game, are mono, 44100hz and 16-bit PCM
Beware though, some are different. 22050hz and 32-bit float for ex.
And the sound files should be almost same in length , or so i've read, that i'm not sure.
Replaced some sounds myself, and at first it was a hassle to get it to work.
@Mackyn1878 Does the game work without mods?
Try that if you didn't already, then we know if it's mod related or game related.
If mod related, you might have to redownload the mods you use, to be sure.
If it's game related,(if vanilla game doesn't work or work correctly) if you have gta on steam, do verify cache.
I don't know if you own the retail, if there is such thing, as verify or something similar, with retail , you might have to uninstall the game en reinstall it. (again if it's game related) If vanilla game works (like it should) no need to verify or so....
And about your specs, which graphics card do you have? (also did you update the drivers to latest)?
@syoxu
Are you using the latest scripthook V?
And the most up to date versions of the mods you use?
Try setting your screen to borderless window in the ingame options.
If none of this works,
i suggest you post some logs here.
Use www.pastebin.com
@ArmaniAdnr
Changing a vehicles seats should be avoided, if a vehicle is originaly a 2 seat , 4seat, van, truck,
i mean these are typical features a vehicle has, for most compatability you should only replace vehicles with the correct features , meaning, a van by a van, a truck by a truck, 2seat--->2seat , bike-->bike,... you'll get the idea..
Although i do not fully understand what you mean.
but you do have a entry in vehicles.meta
<numSeatsOverride value=
The characters sitting position in a vehicle is determined by
<povCameraName>
And possible but i'm not sure
<flags>
and
<type>
@zyankenta
You can manually change the pedvariety- and carvariety- multiplier in settings.xml
default max is 1.0 , mine is set at 2.0 , but i use mods that changes variety in general too.
You say you mixed some vehicle and pedestrian files? Which ones?
Couple of mods that change variety,
These increase variety in general
https://nl.gta5-mods.com/misc/world-of-variety
https://nl.gta5-mods.com/scripts/lively-world
And these traffic only.
https://nl.gta5-mods.com/misc/versatile-traffic
https://nl.gta5-mods.com/scripts/dlc-vehicles-spawn-on-traffic
https://nl.gta5-mods.com/misc/southern-san-andreas-exotic-popgroups-ymt-803cba20-ebff-4a21-82a7-b0d70ab9a39a
I hope this helps.
@Mackyn1878 What are your pc specs?
Also are other games working fine (after you had this glitch)?
Could be faulty hardware , by the looks of it, but then it would show in other applications too.
You don't have enb, and what about other mods?