a 25" Pickerel isn't anything to laugh at (i think they are a ton of fun), but if your looking for big fish, you have to realize that your the numbers of fish you might catch will significantly decrease.
If your looking for big fish, might as well target pike....We have a number of tremendous big-pike fisheries here in the area.
Schroon Lake, Paradox Lake, Eagle Lake, Sacandaga Reservoir, Lake Champlain, Lake George and Saratoga Lake all have targetable populations of BIG toothy critters.
In terms of tackle, For your tipups, I would go with something like a 25lb flouro leader to a #4-#6 treble or quick strike rig. Put a good-sized split shot about 12 - 20 inches above the hook. Your going to want to use the biggest bait you can afford...or jig up your own bait on site with a hali-jig tipped with maggots...perch and bluegills do work as bait for pike.
Locations - start at the weedline and spread out. Put a couple right along the outside weedline, maybe a few deeper and one shallow. The baits don't have to be close to the bottom, but should be at least halfway down.
Now realize that this is a low percentage kind of fishing, you might not catch fish every time out, but the rewards are more than worth it.
An alternative would be to fish the same locations with a 10lb leader and #10-#14 treble and medium sized shiners, you will catch alot more fish that way, they just might not all be big pike...