RAM?

I think Forge creates a new droplet because it needs a fresh installation.

You can choose the 512mb option but you may run into problems with composer running out of memory.

You can fix this by adding the following script to your recipes and running it. It creates a swap file for when you run low on memory.

if [ -f /swapfile ]; then
 echo "Swap file already exists."
else
 sudo fallocate -l 1G /swapfile
  sudo chmod 600 /swapfile
  sudo mkswap /swapfile
  sudo swapon /swapfile
  echo "/swapfile none swap sw 0 0" >> /etc/fstab
  echo "vm.swappiness=30" >> /etc/sysctl.conf
  echo "vm.vfs_cache_pressure=50" >> /etc/sysctl.conf
  echo "Swap created and added to /etc/fstab for boot up."
fi

From what I have found out so far, I think I found the answer, the Forge option doesn't actually do anything with the server, it just lets Forge know what the server is capable of.