Datacenter IP Addressing

My boss recently started making me learn Mikrotik hardware and while setting up a data center I came across a configuration where the DC assigned us a static IP block and that was routed to an IP on a different subnet. We have a vlan assigned to us which has two ip addresses. One ip is the port on the switch, the other is currently assigned to our Mikrotik.

I’ve made this diagram to aid in my explanation:

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Basically due to this IP addressing scheme I need a little assistance with the configuration of the RB750G we have at the DC.
Here are my questions:

  1. I’m trying to keep NAT/PAT in play, How can I maintain a NAT/PAT configuration but at the same assign a public ip to a server (such as a nameserver).
  2. I was trying to keep NAT as a layer of security. Am I trying to complicate this setup by trying to keep NAT/PAT in this configuration?
  3. Is there a better way to do this setup? I need an internal network as some of the servers I run do not require public IP addressing