So, keeping track of which device on your network belongs to which MAC address, and reserving an address for each, is that what you mean by ‘annoying’ - the administration of that?
That's the easy part. Plenty of applications (such as bittorrent clients) use randomized ports. So you have to either disable that, manually add the port forward every time you start the client, or let UPnP handle it, because you don't let any untrusted devices or apps onto your network.
And multiple devices on the network may need the same port forwarded at different times, such as multiple games consoles.
