Here's some ideas on things to consider buying:
FooF tin #7--it has Silver on Offense and Pale Green on defense so you can split it with your wife.
RoA tin #1--Red on Offense and Pale Green on defense for your wife's deck.
FooF tin #4--Blue on Offense but includes Jacob who is a nice addition to a Silver offense and Brown on defense for your deck.
Priests does not have a ton of cards for those brigades, and the ones you might want for your decks (Protection of Angels--Silver or Forgotten History--Pale Green) you can easily trade for so I wouldn't worry about buying Priest packs right now.
There are a few nice cards in TexP that you might want for your decks:
Grapes of Wrath -- Good dominant
Mayhem -- Evil dominant
A Soldier's Prayer -- Red enh.
Asahel -- Red Hero
Gomer -- Brown EC
Image of Jealousy -- Brown enh.
Angel of Warning -- Silver Hero
The Pale Green in TexP is all about Magicians and I'm guessing your wife's defense is more based on Assyrians being that you have the older cards right now.
Some Disciple cards you may want for your decks:
The Rabshakeh's Threats -- PG enh.
King Amon -- Brown EC
King Manasseh -- Brown/PG EC (so you might want two, one for you, one for her)
Gabriel -- Silver Hero
Centurion at Calvary -- Red Hero
Obviously there's more cards than those for the brigades you are playing but that's just a list of the ones I would look for if I were trying to update decks that have already been built with those brigades.
My advice would be to buy those tins I mentioned above, and then buy Disciple and Treasures packs next. Even if you don't get the ones you need in the packs, most of those cards have decent trade value.
Hope that helps, glad you are able to get back in the game! Have you checked the Cactus page to see if there are any tournaments in your area?
Justin