If you need fast hosting, it should be on SSD drives first of all, and secondly - use powerful Xeon processors to handle the entire load quickly. I'd recommend buying vps hosting https://www.hostforweb.com/vps/ since you get a dedicated server with a convenient control panel. If necessary, such hosting is easier to scale for the projects you need.
In your case, it would be better to buy one with 6 GB of RAM since the more RAM, the faster the tasks are processed. You should have about 120 GB of storage space, even if you have a vast database.