I have a few of the alternative sculpts from Infinity (Hippolyta, Valkyrie and Shona Carona) and might pick up Maximus and Mendoza. They don't seem to come with all of the cards though. If I want to play a team (with someone else Aristeia box), what do I need to buy? Can I print the model-specific tactics cards? Should I buy the Advanced Tactics Deck? I'm looking to have a casual team that I can play on a games night without having to buy the core and expansions for models I already have.
The tactics cards come with the expansion boxes, they don't get reprinted in the skins/alternate models. I think all the tactics cards are on the website so you should be able to print them off and play with them outside of tournaments, but I don't know if the core deck is available that way
I would just buy the Soldier of Fortune Expansion. Very balanced team and you should be good to go if a friend brings the core box. Costs around 30€ iirc, so not a major invest. Advanced tactic decks are good fun, I would buy them. All depends on how much money you want to shell out.
I wrote a shopping guide on my German blog which should work with Google translate: http://arachnet.de/aristeia-shopping-guide/ My suggestion is to get the Core Box for some very good characters, a HexaDome, the basic tactics, dice etc., the Soldiers of Fortune expansion and the Advanced Tactics Decks and your have a solid start.
Soldiers of Fortune box was my first purchase. After a few games played sharing a friend's core box, I felt I wanted my "own" team, and Soldiers of Fortune looked like a nice option. I didn't stopped there, of course You need a standad deck to shuffle your Aristos' specific cards in, but if you play with a friend who owns the core box, he should have one to lend (possibly two, if his core set contains the extra foil deck). Otherwise, you could buy the Advanced Tacktics pack, that contains two alternative standard deck, one more focused on aggressive play, the other more focused on card management. To use alt-skin of Aristos that you don't own in plastic, you could print cards from the website, as you're saying, OR -since extra Aristos boxes contains all cards in FOUR languages- you can check if some friend owns the box that contains it and if he's willing to give you cards in a language he doesn't need (and hopefully you're able to read )