As you've seen on my swaps I like to point out and welcome newer tyers to the swap. I'm currently a member of 2 other sites - one that was once THE site (FAOL) and is now dying as a site, and another (Fly Fishing Forum) where swaps had become few and far between because of swappers AND hosts disapearing from the face of the Earth during the swap.
I come from a skill teaching background and try to 1) tie a couple patterns not one and give some fly tying material gifts when I host - after 50 years of tying I have enough material to last until I'm 150 years old and 2) a fact sheet with a short history of the patterns I tied along with it's recipes and tying directions. I am doing all of this to encourage "the new generation" of tyers and swappers. This also gives a little more value to the swappers. Also, when someone tells me taht they are new to tying I will - help them find a good pattern to tie (if needed/requested), will PM the newer tyer with a list of hints/tips/tricks/traps in tying their pattern choice, and provide a PM feedback after their flies are received. This feedback includes what they did well and where AND HOW they can improve. I did this on the Beginner Swap series a few months ago on this site. This on-line classroom also helps give the swap a little value as well. If this works as planned - good, if not - well I won't have the preasure of living for the next 90 years to use up my material!
I would STRONGLY suggest that hosts, if applicable, openly offer/promote their fly swap as open to new tyers - highlight this fact on the swap and openly offer assistance to anyone who is interested. I also offer support to those new to swaps - swaps can be a little intimidating to some, thinking that they do not tie well enough - even for a more experienced tyer.
This is what I've learned from 10+ years of participating and hosting swaps and I hope this helps.