Perhaps you cant even main your favorite type because it just doesnt seem to exist in the TCG
Irida (Supporter) If you're playing a Water-type deck, Irida is an ideal support card, capable of healing 40 damage for each Pokmon with an attached Water energy
This card acts too as a cute way of protecting your LP but it isn't exactly reliable, since it depends on a coin toss ( but it does make a lot of funny burn wins) Dark Spirit's Mastery x3 This card is arguably the best card of this archetype: Acts as extra copies of Loading
About which packs to buy, actually it does not matter that much since the probability of getting what you want is low, but, to maximize it, Id recommend getting Amonkhet for Hazoret the Fervent, Glorybringer, Ahn-Crop Crasher, Magma Spray and Sunscorched Desert
The gold Ultra Ball blends practical value with collectible appeal
It has protection from White and Black, gets a +1/+1 counter on it whenever you cast a creature, and makes creature spells you cast one mana cheaper for each +1/+1 counter on it