Geoff,
Good to hear that the fish like the flies
catching on self tied dries, magic!
from an aesthetic point of view, one thing that I think would instantly revolutionise your dries would be to focus on the quality of hackle that you use.
Next to (possibly) your vise I think the most expensive purchase is a good quality cape, well actually capes
Capes are a topic on their own but costs can be reduced by the fact that they can be purchased in 1/2 capes, 1/4 capes, neck patches & even packs of select feathers. There are also various 'makes' and grades, colours and type of chicken donor to choose from.
It's a night and day result when you have a quality hackle with the correct barb length for the fly being tied.
There are much better positioned guys on here to advise of what is currently on the market as due to the fact that I don't tie too many flies and capes last an age then it's been a while since I've bought one.
I get a feeling that I should be tying these dirty dusters
but I don't have a dirty badger............cape.
Yan