As with so many things, asking for anything favorite on this forum is like asking "Which one is your favorite child", hence a hopeless debate 
But here's the shortlist of the bulk blends I buy regularly:
Lane Limited 1-Q: It's just a regular staple with a consistent quality and flavor profile. The room note is acceptable and reminds many people of "what pipe tobacco is supposed to smell like". I carry it with me all the time in my pouch #1.
Lane Limited MV-1000: A nice Virginia with a little vanilla toppping that is right up there with the 1-Q. But less sweet, a little more lemony or grassy thanks to the Virginia. Just like 1-Q, non-offensive and smokes easily. It is one of the two tobacco's loaded in pouch #2.
AC Peterson Mark Twain: A nice cavendish with a caramel, marsh mallow kinda aroma. Even the occasional wiff of chocolate has been known to make itself known on happenstance. It is the other tobacco loaded in pouch #2.
Cornell and Diehl Autum Evening: A relatively recent addition to the bulk jars. I purchased one tin and the maple sweetness was an absolute success in the Autumn evenings. I guess they chose the name well. Given that it is also quite tolerated by the better half, it has earned its rightful place on the shelf.
MacBaren Vanilla Cream loose cut: Since this is available in 16Oz. containers or bags, it gets added regularly to my bulk purchases thanks to its ability to appease the wife and lure her to come sit out on the patio swing with me. It's vanilla aroma has an irresistable call to my lovely spouse, who loves all things Vanilla. Now if I could only find a way to load-up those darn Glade wall-plug things with this, I would be a happy man.
Kendal's Kentucky by Gawith, Hoggarth and Co: This fine shag cut is just my nicotine princess. Either smoked by itself in a smaller size bowl or added to any of the aforementioned tobacco's, it tends to be able to curb my nicotine cravings and hence is able to keep madness at bay.
As you notice, most of my bulk purchases are aromatics. I purchase most other things in tins, although I have a couple of jars of H&H LJ heart Virginia, some Louisiana Red and some Old Joe Krantz and Haunted Bookshop from C&D stashed away somewhere
Hope this gives you some more ideas. Happy puffing ! 
"The fact is, squire, the moment a man takes to a pipe, he becomes a philosopher. It's the poor man's friend; it calms the mind, soothes the temper, and makes a man patient under difficulties. It has made more good men, good husbands, kind masters, indulgent fathers, than any other blessed thing on this universal earth."
-"Sam Slick, the clockmaker" aka T.C.Haliburton
