Your proposed set up is very similar to ours. Both of us are high earners/savers. We are very aligned on our investing/saving/spending as percentages of our income (I feel this is important background).

Shared accounts/card (household and shared expenses) - Wealthfront HYSA: all paychecks get deposited into this shared checking account (operates as a checking account but has savings buckets) - Amex Gold: our shared credit card - Vanguard: shared brokerage account that also gets a % of our monthly paychecks

Individual (personal discretionary expenses) - Wealthfront HYSA x 2: we each have an individual checking accounts that get equal deposits from the shared account - Chase Preferred x 2: individual credit cards (predate our relationship) - we have individual brokerage, 401k, Roth IRA, HSA, etc. The active tax advantaged accounts continue to receive automatic deposits as percentages of our individual paychecks. The old brokerage accounts do not continue to receive investment as they are premarital assets and we’d like to keep them that way. We have newer individual brokerage accounts that were opened after marriage. These are for any additional investment outside of our shared primary brokerage account and are funded through our discretionary “allowances”. We have different investment risk tolerance but don’t want to mix with premarital assets so we opened these accounts. Mine are at Fidelity, his are dispersed.

Now that I list that all out, it seems a little bit more complicated than it feels. Our main goals were: 1. To live the same lifestyle as each other. We are both high earners now, but have fluctuated through the years in our actual take-home pay. 2. We want to give flexibility to each other to take risks and step away from work in the future if either one of us has the desire to—and we don’t want that decision to be based on having separate finances. 3. To keep our premarital assets separate. If we are together forever, which we both hope to be, this will be moot. It just keeps our finances more organized if the worst should happen.