The depth of the pockets is not part of the Kelly equation. If you bet twice Kelly (even with a profitable system), you are mathematically guaranteed a ruin, no matter how much money you have initially. That's because the Kelly bet is always proportional to the size of the account. Quarter Kelly is a reasonable leverage. Yes, you can. I believe these figures are invariant to the system. For example, with full Kelly, you have a known 20% probability of losing 80% of the account.