What do I need to build a "Cube" for Kitchen Table Deckbuilding.

Hello everyone,

Me and my kids (6 & 8 yo) would like to get into the game but just for fun at Kitchen Table level.
When I was kid what really hooked me up with the game was building my own pile and have fun with my siblings and friends. I want to to repropose this experience to my kids without buying tons of sealed expensive stuff.

The local game stores are selling lots of ~1000 drafted crap random cards (C/U/R, no trainers, no energy) for cheap.

I was thinking to buy one of those lots and add 20 energies per type plus a list of selected trainer cards.

I was thinking to have a pool of ~20 Trainer cards as base per deck (so ~12X of each) to make the decks decently consistent. Which good-overalltrainer cards should I get?
I was thinking of:
-4 Prof Reasearch
-4 Nest ball
-4 Ultraball
-What else?

Thank you very much for the help.