I've run four rods comfortably off my boat, YMMV. I'm a beginner and most of my know how has come from a couple trips plus reading here.
One rod with an umbrella rig. You can buy them pre rigged or make your own. Use inline sinkers to change the depth of your rig. Run two if you like,
One rod with a mojo 3-5' under a three way, and a trailer, such as a smaller bucktail or a 6"-9" storm, about 5' behind the three way. You can change the size of the mojo to change the depth of it. IMHO heavier is best, I'm running 20 ounce mojos and will be buying larger ones when finances permit.
Another rod with maybe another Mojo rig, or a stretch 25 or 30. Or you could use an inline sinker and run a naked storm.
So far I've only caught one fish on the troll. It came off the storm being trailed behind a mojo.
Try running 2 umbrellas off your corners. Add an inline to one or both of them to cover more of the water column. I put 4 oz. chutes with shads down the middle. The type I like have 2 oz. bucktails on two of the side arms. ( I can't remember what brand).
Two 20-32 oz. Mojos on a 3 way with storms, tomics, or parachutes off out rodders. This should be enought weight to keep them underneath your umbrellas. If you are in search mode you can run daisy chains above the Mojos, which puts a lot of baits in the water. Braid or wire would help these get down.
Then run two long/shallower lines behind the umbrellas: You could use Tandem parachutes, stretches, 9" Storm Shad with a 4-6 oz inline, Spoons with an inline.
This is the spread I pull from my 20' boat and it has worked decent this season. Keep changing (size, color) the trailer boats behind the mojos if they are not producing.
I rarely if ever run umbrellas, so here is my approach:
Wire lines off the rear corners (could be mono or braid) with heavy weights. Some put Mojos off these up to 48 oz on 3' droppers from 3 way swivels. 6-15' leaders off the 3 ways with various things running behind including: 6" storms, bucktails, double bucktails, tomics, spoons, bomber A, etc. On the gunnel rod holders we put something for the mid column on heavy mono like daisy chains, tomics, 9" storms, parachute rigs, etc. (I think folks put umbrella rigs or stretches here, but I don't run streches much) From the center positions we like to run heavy mono in the shot gun WWWWWTFB like a 4 oz swivel head bucktail with 6-8" grub, 9" storm, spoons, etc...
Hope this helps.
Tight Lines & Happy Holidays to All,
Coastal Conservation Association-Virginia