You don't
have to spend the adventures. If you absolutely cannot stand to miss the opportunity, there is a mechanism to spend multiple adventures in one action. There's a job board in town that uses 5 adventures at a time, and you can work at the bar for N adventures. You can straight up trade adventures for meat in one click. Log in from your phone, spend all your adventures at once, then log off. Or write a script that will log in and spend all your adventures for you, without bothering you at all. It's all https requests.
The 40 rollover adventures combine with daily consumption limits to give you an easily attainable 200 adventures per day per character. That's about 3 hours of play, if you aren't using automation aids. If you accumulate adventures to the cap, and then play them all the next day, you can use about 360 adventures. At the risk of the statement haunting me later, 200-360 should be enough for anybody. If you want to play more adventures, you can always play more than one character. Or, as you mentioned, if you want to play for more time, you can spend more time playing each adventure, to be more optimal.
You can't ever escape tradeoff #2 if your personality is susceptible to obsessing over things. If you play Tetris too long, you might dream about falling tetromino blocks. The important thing is the Asymmetric folks aren't trying to profit from obsessive player behaviors by throwing wildly non-synchronized countdown timers on everything.