Hunter and Warden are both characters that can solo extremely well and also can work together decently.
As for crafting, I have found that the best pair of vocations for 2 characters is actually Explorere and Historian. Why is simple, between the two they can gather crafting materials from all craft nodes in the wild and provide these materials to alts who then supply any other crafted materials you don't want to buy. All other vocations can then be done by alts that you don't need to actually play but simply sit in town and craft from materials provided your main two characters.
The Explorer gathers ore and wood and tailors both light and medium armour (used by 6/9 classes). The Historian gathers specialized nodes and uses those materials to make potions and scrolls which can then be used to help you level easier. Much of the materials that the two of them gather can also be sold on the Auction House (AH) or traded with other players to get them to make items you don't have a crafter for.
At some point, you may want a Yeoman alt that never leaves Bree or The Shire. They simply farm and cook and provide food to the toons you play.
Shields, weapons and jewelery can also be made by town based alts if you want or purchased or traded for on the AH.
[CENTER][B][I][COLOR=yellow]LOTRO proves that Middle Earth is Hobbit Forming![/COLOR][/I][/B][/CENTER]