20-35" for a leader length?

...Yer gonna miss a lot of fish with that length, my friend. If the water clarity is poor, I would cut that back to 12-14 inches from the swivel to the terminal gear. If the water is very clear (over 3ft. vis. I might lengthen that to 18 20". Several factors should be explored here.
I have seen a large piece of pencil lead
firmly crimped onto the mainline and a 3ft. leader with the result usually being the lead is stuck on the bottom,the presentation never gets into the "zone" and the mainline breaks (somewhere) and quite often all gear is lost!
Consider:
...using shorter leaders with micro shot rather than one large peice of lead.
...smaller floats and swivels......(more fish)
...using a float that is not FIRMLY attached to the mainline(sometimes if you are hungup on the bottom and play out some line into the current, the drag on the float will often unhook you)
...smaller, good quality swivels (they get hung up far less)
...squeeze the pencil lead on the mainline, or leader
just enough to hold it in place. (if you get hung up it will easily slide without nicking the line and often this will result in saving the gear)
...Use only enough drop from the float to the terminal gear to ,be slightly above the bottom. If you want to slow the drift, you can add a bit more weight. Don't let the float lead the presentation any more than necessary.
...work an area from top to bottom, so you'r not casting upstream.
If you cast into the trees or a bush, tighten your line VERY slowly, until the line is out of the water,then vibrate your line by quick wrist actions.....DO NOT PULL....Most of the time it will come out on it's own.
...If you are hungup on the bottom, it can often help to go upstream of the hangup and then VIBRATE the rod, don't yank on it.
.....Practice your casting at the park with targets......You will save yourself a lot of $$$
....Losing gear cuts into productive fishing time and using too long a leader to protect your float will likely result in less fish top the beach.
............................Ortho............... 8)