The goal of perfect draws combat is to simulate the types of stories you see in card game anime. So this meant making some changes to expected card game rules to benefit the narrative pace over just the mechanical expectations.
So for example - in these stories, players usually have the counter avaliable when it's useful to them - atleast until a certain point where they've expected their resources. This allowed us to replicate that and create a pseudo "second health bar" that helped keep powerful effects in check despite open ended card creation. Originally we actually had them exist in your deck (while still acting as open ended roll based counters) as a thing called "trick cards". But too often this led to underwhelming stories that felt like a normal tcg yes, but not like a tcg anime.
As for staples - this was similarly to benefit the "duel writing". Certain effects needed to be accessible to certain decks at certain times, so staples allowed us to balance that without requiring too much consistency from the main deck. Your deck is always going to represent the "most important" cards of a theoretical anime deck because ttrpg storytelling is naturally condensed. Effects like pot of green or a generic normal monster are generally always assesible when you need them to be - so letting people have them on hand keeps stories going at pace. It also helps significantly with deck construction since making cards is already a time consuming process compared to the rest of starting the game up - needing to make fewer cards helps that a lot. Additionally, it gives players easy ways to know certain things about their deck and protect against their weaknesses as they go without having to use a whole card or find that card in each moment it's relevant - decks that don't play warriors benefit from staples that create warriors for example. Finally, it helps keep card games fast - only one action per turn doesn't feel significant or similar to these stories, but letting players use multiple easily led to a lot of complicated, swingy, and wheels pinning turns. Staples mean players get to do one significant thing alongside one less significant thing, so their turns feel impactful but don't take too long.