Very early in our marriage, long before MMM's blog, we realized that I was a saver and DH was a spender. So we worked out a system which made sure that all expenses, including saving, were covered before spending could begin. So I could relax. We then managed personal spending by establishing allowances, within which a person could spend without judgement. So DH could enjoy spending and I could stay relaxed. We also instituted a "top up" process whereby the "family" would be happy with a certain level of say, a sound system, and if DH wanted more bells and whistles, he would cover it out of his allowance.
Since we've had years now where income far exceeds expenses, and being busy at work reduces hobby time, we've not been as conscious about a saving/spending system. Post - FIRE, it might just be as simple as getting back to what worked for us years ago. Determine income, cover required expenses, and allocate the fun funds. Huh!