I personally play a minimum of 6 cards and a rough maximum of 10, with the caveat that commanders like Lord Windgrace are going to require more than commanders like Kinnan, Bonder Prodigy
For those of you who may not have been playing prior to the sideboard change, we originally shrunk sideboards in Best-of-One to seven cards with the release of Strixhaven: School of Mages
It also allows you to check when and where cards have been reprinted and confirm format legalities, and it even features community options to rate cards or comment on them to open up discussion
In Boros legend decks, owyn can clear the path for a massive, protected attack that puts the game firmly in your favor
With so many variables changing for that archetype I suspect I am best off waiting to see what it looks like once the dust has settled somewhat rather than trying to predict outcomes now
The first edition holo Charizard is particularly valued for its age, limited availability, and the recognizable image of one of Pokmon's much-loved mascots