LBL is kick ass. Don't hit turkey bay though! Get a road map from any visitor center and hit all the roads starting with a 3... IE... 301, 320, etc... They are also drawn differently on the map for clarity. They have been doing some renovations down there, so a few of my recommendations may have changed since last I was there. I imagine they are still dirt, but could have been plowed and cleaned up which takes some of the character away.
Basically you have the main road down the middle with gravel roads branching off those. Well, in between those gravel roads are the unmaintained forest road. We have a group that has ridden there quite a few times and have ridden just about every worthwhile forest road there.
350 loop is a must see and is probably the best loop at LBL. Loop 357 & 356, also a must see. 373, 374, 375 all close together. 224 is cool and really rugged. 377 & 378 are great out and backs. 322 & 324. 322 has some watershed bumps that are jumpable. 141 is cool, mostly gravel/dirt mix. 318 & 308 are cool. 304 and 305 are good also.
Basically, if you look at the map, you can link everything together and go from one end to the other. Using gravel roads and the main road to connect the forest roads.
Also, I'd be happy to come along if you let me know the dates of your visit. Might even be able to round up a few more riders if you want.