So will throw up a more detailed description of why this is a no, and also the hardware shit we haz cuz people seem to have no idea even though it's public knowledge.

Were running on a server that has;
Intel Xeon E3-1270 v3 Quad Core Processor
32GB ECC RAM
2x 2TB Sata 6Gb/s 7200RPM HDD's

Now, firstly, processing power isn't an issue, we don't have problems with running out of CPU, in fact our CPU usage is generally relatively low in comparison to our ram usage.
The RAM is where the problem lies. The ram is split up into 3 essentially due to the fact we use 16gb of the RAM as actual RAM, 8Hb as a RAM drive, which is basically a method where the servers software treats it as a disk drive due to special shiz we have set up. The reason for this is a HDD or SSD just doesn't cut it when it comes to speed, we time out at backups now, with even slower speed of that shit, it'd be even worse. And a final 8Gb that's reserved for running the TS3, website, etc.

The RAM we're using just as volatile memory, is normally fine and we wont be running out of that, but the RAM disk is where our problems lie in terms of expanding the server. Due to the small size of the RAM Drive it limits the total stored memory the server can take up. And where we're at now means we can't just go adding large new worlds as big as our others. The old world just by itself is 1.5Gb.

We're currently running with about 20% of our space free, which might seem like a lot but when times come such as creating a new creative world, the old one stays for a while whilst the new one is having things moved over etc, which can then take up a bunch more space. so we generally like to keep enough free space to allow that sort of thing to take place.

So there's a summed up story of our server and why we can't fit more new worlds. Some of my information may of been incorrect, at which point I'm sure Stoux will correct me on it