I used to run a mono sphere lore deck with aragorn, mirlonde and denethor. Only problem I had with it was low initial willpower for questing made some quests rough early on. (drawing a second stone giant on the first turn for the 2nd quest in overhill underhill comes to mind in particular)
But once you got a rivendell minstrel and a song of kings going to get blade that was broken out, it really started to rock. Amazing card draw with mithrandir's advice. Scry with henamarths, denethor, rumor from the earth, and risk some light. Best allies in the game in terms of cost for ability. (Eg: Wandering ent, celeborn, gildor inglorian, mirkwood runner, warden of healing ect) All that AND incredible threat control with lore-agorn's reset ability.
Competitive solo deck without glorfindel is easy to do.......glorfindel is just way to powerful for people to look beyond is all. It's actually my personal opinion even though I run him in my main solo deck atm, that he should never have been printed with the threat cost he does. He should have at the VERY least been an 8 or 9, and only had 3 MAYBE 4 health and only IF his threat was increased to reflect that. And even that would be really pushing it.......
No two ways about it though, Glorfindel is just to much bang for your buck.