I'm mainly a coinshooter also, but if I wanted to find some relics too then the first thing I would do is check the ground conditions to see a few things, like, is there a lot of iron/trash, how highs the minerization, and what are the first few non iron targets I dig. If there's not a lot of iron/trash then the factory preset coin pattern will be more than enough accepted screen for hitting the wide range of higher conductivity targets and you won't have to listen to excessive noise.
If there is a lot of iron/trash then you can go with two screens each depending on how much non-iron targets(high conduct) you are finding and whether or not some are coins. If there isn't a lot of good tones and the pickins are going to be really thin then Iron Mask is a good idea because the affect iron has on the non-iron stuff is enough to make it worth looking closer to it. A coin, button, or other similar object will pull some goodie's signal to the iron side, if the screens accept is not low enough in Iron Mask or a custom screen set up similar to Iron Mask then the good targets will go nulled out and missed. So, running Iron Mask in this situation would be a possible strategy due entirely on the scarcity of good tone targets.
Now, as I said if you are already finding the higher conductivity tone targets and it looks like you won't have a problem with finding tones worth digging then you may just want to cherry pick you way through the field with the chance that each signal is a possible relic(you might be surprised what the commitee thinks is a relic), and sooner or later your gonna hit some coins. If you hunt in Iron mask in this preferred case scenario you really won't be hurting yourself, that is as long as you don't get fixated on the oddball tones just because there next to iron, the chances of them being junk probably better then them being coins. Again, this based on the abundance of good tones.
There is also the iron relics, tools, like hoe's, pitch forks, shovels, and others along with things like horse shoes. These are things the committee may want also so at some point you probably should start digging iron, of course low Iron Mask or a clear screen would be the way to go for this. The relics we find that don't impress us may be exactly what the committee would love to have like the old pots, pans, forks, spoons, dinner knives, buckles (actually I like old buckles), but things like that they want and these targets will hit all over the screen. They also would like buttons.
Anyway just a couple additional ideas, hope this helps a bit, it really sounds like a great site to hunt.
<b>GL/HH</b>