I'm with Skip on using the #2 chenille all the way down to 1/64. Some of the bigger chenille's I wouldn't use on the smaller jigs. Using the size 0 also works great from 1/64 on down to fly sizes. Barlow also carries the Bugger Yarns, works nice on some patterns.

Really if you like tying the smaller sizes now would be a great time to began learning to work with dubbing. There are tons of dubbing to use on different tyes plus making your own.