I have to do something that requires fast internet speeds and latency. Using the Tor network is too slow. 

If I just use Mullvad and not Tor, how much is my privacy at risk?

if you're not doing anything illegal, Mullvad is fine.

buy a rdp or vps

There is no specific company that can be trusted to hold your data and not sell, or give it up when required by a law enforcement agency. 
Mullvad specifically states that they do not hold logs, and that they are directly pointed to /dev/null on all of their systems, but you can never honestly take their word for factual information.
Moving forward, Tor is slow, and yes it can be absolutely painfully slow at times, but slowness reigns over in presidency when compared to security, and privacy of a fast connection.
Next, I would highly suggest that you buy a RDP, or a VPS that you can login via remote Xorg server, or even something more simplistic such as just straight SSH...
It depends on your use cases, but first and foremost -- you should highly recognize that regardless of what you do... Tor is still the best option over everything.
VPNs will only get you so far, and if the VPN company gets subpoenaed then you're essentially fucked....

Best Regards

Use a VPS and a VPN just in case.

(November 12, 2022, 09:39 PM)Gum8 Wrote: I have to do something that requires fast internet speeds and latency. Using the Tor network is too slow. 

If I just use Mullvad and not Tor, how much is my privacy at risk?

Mullvad and a privacy altered browser and you are pretty good to go, basically saying I would not use google.

depending how much time you have to sink into it, firefox with containers and maybe hardened would be my route

Yeah, as the others already said, Mullvad should be fine by itself. Maybe a simple proxy chain and thats it

VPS > TOR > VPN (Mullvad). This is the way some of use the services