I haven't seen too many trolling the Conny but when I have they're 40-50 back I'm guessing. At it's deepest I'd say the river is only 8-9'. This time of year though you'd do much better trolling the outer west break wall. Sunrise till 10ish then late afternoon till sunset are your best times. I've always stood on the break wall casting blue & silver 2/5 little Cleo's.
I've only trolled at Conneaut for steelhead. Typically we will troll around the outside of the breakwall, in the harbor and ship channel, and up the creek. Just depends on where we find them biting.
Spoons could be anywhere from anywhere from 50-120 back. but most of the time they are about 100' back. We use a variety of spoons, light ones like little cleos, michigan stingers, etc. We use heavy spoons like krocodiles and our old go to the blue fox pixie spoons.
If you've never fished conny, there are 3 navigational concerns/points to be aware of. Enter/exit the harbor to the lake at the north entrance in the breakwall. The west breakwall entrance cannot be used by boats as the sandbar has filled in that corner of the harbor and what water there is is very shallow. Not sure about the east entrance.
The rail bridge at the dock where the river enters the harbor/ship channel is very low. I believe the official clearance is 3 feet. So if you have a low boat you can get under, a big water boat won't so approach it with caution.
You can only travel up river to the rail bridge just south of 15th street. You can cross under the bridge and there is room to turn around in the pool. But it gets shallow just upstream from that bridge, I've watched people bottom out a jetski there and get it stuck.