Acquiring cards to get 3+ people building decent decks.

I'm looking for the best ways to get enough (quantity as well as matching archetypes) cards to get a few people up and running. Myself and two friends have decided to get back into Yugioh after 8+ years out of the game.

We've each purchased a starter deck and a handful of boosters. One has a bunch of geargia monsters, another has a bunch of monarch monsters, and I have a Frankenstein'd deck full of winged beasts and warriors.

As a whole, we don't have NEARLY enough useful spells (8-10 each not including rituals). We have about 4-6 cards for any particular archetype, meaning we have to try and get 2-3 ones to work together. We're okay on traps. XYZ/Synchros we mostly don't have the necessary materials. (1 tuner in ~200 cards) Meanwhile we haven't even started to think about pendulums.

What kind of booster box / starter decks / etc would be a good stimulus package for our gameplay? Eventually we will probably start participating in the local community, wherever it is, so I'd prefer the cards to be reasonably recent and semi-competitive on the large scale.