All the points mentioned so far have been very good and accurate ones. You did not mention how you are tying in the hackle feather, so I am going to add a few things that may be of some additional help to you and others in tying soft hackle type flies, Kebari or otherwise.

Try tying in the hackle feather, regardless of type - soft-hackles like partridge, pheasant and starling or hen and softer rooster neck and saddle hackles - by the tip instead of using the base of the hackle feather. That way you will be winding on the smallest part of the feather with the thinnest most flexible part of the hackle stem being wound on the hook instead of the biggest part of the hackle feather. This makes it much easier to tie the proper sized hackle on smaller sized hooks with what appears to be over sized hackles. Also, doing it this way often makes it possible to skip using hackle pliers as there is a lot of feather sticking out above the hook, and you are gripping the sturdiest part of the hackle feather stem, which speeds up tying considerably by eliminating several time consuming tying steps and hand motions.

If the hackle is still coming out too full for the look you desire, strip all the hackle off of the feather on the away side of the feather with the concave side of the hackle facing up. Soaking soft hackles in water for 20 minuets before preparation will soften the stem and prevent it from cracking or breaking as the hackle is being wrapped. It also makes the above hackle fiber stroking and stripping operations a lot easier to do. Cut off the long feather tip so you have a short square section of the hackle to tie on to the hook shank, which takes less time to tie in, less thread, and creates less bulk on the finished fly for an improved appearance.

Slipping a short length of hollow midge sized body tubing over one jaw of the hackle pliers will help the jaws to get a better grip on soft hackles and other hackle feathers with out cutting through these delicate hackle fibers when gripping and wrapping the hackle by the tip end of the feather. The hackle pliers so modified will still work just fine in all their normal tying applications so adorned. Give these things a try and I believe you will be making faster and better looking flies, quickly enough.

Thanks for these tips!

Sylbaro, click on this link and then scroll down until you get to the title: "How To Tie the Twisted Camel", on Step 4 you can see a picture of how a stripped soft hackle hackle feather is tied in by its tip and wrapped on Step 5. Here is the link I promised: www.tenkaratalk.com/category/tenkara-flies/page/2/

You have to soften the stem by hitting it gentle with something crushing it without compromising the intergrity of the stem