It can make sense to run 23 or 24 men for a little while to start the season. There will be opportunities to fill the roster via waivers, trade, etc during that early season period. But you're going to need the depth sooner rather than later. If a prospect spends at least the first 20 HBD days of the minor league season in the minors, he won't use up a year of ML service time (i.e. you'll still have 3 seasons before arbitration), so if you are going to call up prospects, consider that as well.