It seems to me that with the cost of manufactured foam cutters....talking sheet foam here....there would be a place for a generic set of foam cutters that once you cut it out a snip here or there would be all you need...

Something to cover ....

Stonefly wings..[salmonfly]
Hoppers
Frog
Mouse
Caddis wings
ETC...Etc...

When you do it let me know ...I'll buy...