I strongly suggest getting Moria which will take you to around level 60. If you aren't interested in Warden and Rune-Keeper or the extra character slots, you can just buy the Moria quest pack. If you prefer leveling through action and fighting, I'd recommend skipping Lothlórien. It does include some orc killing but mostly it's quite peaceful with lore-oriented quests. Enedwaith vs. Mirkwood is pretty much about your personal preference. Enedwaith is mostly open plains while Mirkwood is a dark forest area. If you liked the atmosphere of Angmar you'll probably like Mirkwood too. Mirkwood also gives you the instance cluster (three 3-mans, one 6-man and one 12-man) if you like group content.
But I agree -- if you buy all of the expansions there won't be need to buy any of the quest packs if you're just looking to level up. The expansion Quad Pack can easily take you to level 85.