Looking to see if this makes sense for a trolling setup for Lake Michigan.  Going after salmon/steelhead/browns/lakers mostly, not too much walleye.

Two rods setup with leadcore run to the sides (with planers?)
Two rods setup with stainless line to be used with dipsy divers run in between the above rods

Trying to keep the setup simple, but effective.  I don't want more rods or downriggers, as we also use the boat for skiiing/family hanging out, and there's not a ton of room for a full-blown fishing setup plus family and skis and dog and coolers, etc. etc.

We are somewhat newbies and more accustomed to fly fishing, so trying to figure out this trolling gig.

Could you run shortys (5-6' trolling rods) right off the back with your dipsys or snap weights and just run 10-12' trolling rods on the sides with your leadcore?  
You can run planer boards with leadcore, but take a minute to check youtube for board setups, or consider segmenting your leadcore with mono between each color of lead to clip your board to so as to not damage the lead.  Some planer board clips are really hard on the lead.

thanks.   I ended up putting stainless on my old reels, new reels with leadcore and will figure out the planer setup.  Hope to get some salmon this summer.

IME- trolling in those waters produces a fair amount of pike and muskie strikes, which can both sever the lead core line if you don't have a metal leader.