I agree with AG being good for new players. But CA, Ninjas and REZ which are way too expensive decks. Also Phoenix is not really expensive, it is mid budget at most. Pulling 3 Phoenix is way easier than making CA, Ninjas or REZ. Also you will get SRH and Heavy Knight which are always awesome. Besides that, the deck only needs cheap Yaksha and Island. You can jam ECon, SRH, Heavy Knight and get a cheap tier 1 deck with just 1 pack.
Depends on what you want to accomplish. Phoenix won't get you far in the meta anymore, but it's still a very powerful deck, and the set of SRH is crazy good. Part of what you want to look for in a "first pack" isn't just the decks it leads to but the removal. The meta shifts, but removal is always more or less useful.