Turns 1-3: Establish tempo, watch your hand size Early turns are about staying at 5-7 cards
One Piece Card Game Official Starter Deck - Start Deck Red Shanks ST-23
Otherwise, it'll go all the way down
Instead, you will likely want some efficient point removal, defensive enchantments and a quiver of instant speed protection spells to protect your creature combo engines
Yes, that is also the main disadvantage to getting card advantage through drawing cards and yes, discard is also weakened by diminishing returns which card draw isn't, I am not comparing discard to card draw as a way towards card advantage, just stating the facts about cards in isolation
I think an Ikra Shidiqi / Prava deck would want to have a regular token generation strategy and a lot of synergy with lifegain