Encase Dictionaries in nodes?

I’m just getting started experimenting with Dictionaries.
Currently using the Lunchbox nodes, but hopefully will use OOTB node once I get 2.0 rolled out.
Anyway, I’ve got a bunch of things I’d like to put into Dictionaries. These would be used in many other graphs, so I don’t want to have the list definitions in each graph, so I’d like to wrap the Dictionary definition inside a custom node.
Any tips on the best way to do this?
Do I just make a node with the input as the Key(s), and the output as the value(s)? Or is there a better way?
One reason I ask is that I do have one dictionary where I’d like to make two-way. In other words, one node would use the first list as keys and the second as values, but I need another node where the second list would be the keys.
Would I need to have one custom node to define the list and two others to define the Dictionaries? or can I combine that somehow.
(Hope that wasn’t too confusing.)
Here’s an example:
I need to translate from numbers to their ordinal:
But I also need to pass FIRST and return “1”

I’m a little confused on your second question, but yes, it should be as easy as wrapping a dictionary inside a custom node. You would just feed the key and it would output the dictionary value.