A cardholder is one of those things you buy once and use every day for years, which makes the wrong choice more annoying than most. Before picking one, it helps to think about how you actually carry things rather than how a product photo makes them look.
If you carry cash regularly, look for a model with a dedicated bill strap rather than trying to wedge notes between cards - it's the single biggest source of bulk and wear. If you tap to pay constantly, check that the card sits close enough to the surface for reliable NFC reads through the shell.
Capacity matters less than most people think. Most cardholders that claim to fit '10+ cards' are only comfortable at 5-6 before they stop closing flat. Count what you actually pull out in a normal week - for most people it's 3 to 5 cards plus an ID.