It's early in my first campaign, and I paid extra and made event choices to get my morale up to 31, in the Spirited range, where the tooltip in the management screen says I'll get 25 resolve every combat round. I did, in the first mission I ran after getting to that level of morale. Every mission after that one (4 or 5 I think), I'm only getting 15 resolve per combat round - that's what the tooltip in-mission says, and when I pay attention between rounds, that's exactly what I get, 15.

Bug? Or am I missing something? Anybody else seen this issue? Maybe I'll let my morale drop down to Steady and then bump it back to Spirited to see if it will unstick a stuck flag or something.

You may be right.
Already when we have 50 morale, paying to add leasure room in spaceship seems to be completly waste of time and money: when we lose morale those rooms seem useless.

Confirmed bug. Went to Restrictive payroll for a month, dropped to 29 Morale, ran a few missions, 15 Resolve/turn as expected. New month, went Extravagant again to take me to 31 Morale, Spirited, should give me 25 Resolve/turn. First mission out, still 15 Resolve/turn. Welp. Guess I know I don't need to spend any extra money or make any morale-increasing choices for the rest of the campaign. What a drag, that was an interesting mechanic to deal with.

It's definitely worth it taking the "high spirits" pilots on missions if you want to use morale boosted abilities. They pay half cost for their precision strikes. And having the morale oriented rooms makes it more likely you'll get high spirits during the travel mini-choice story lines.

That said, it always seems to be your worst pilot who gets the dang tag and never the ones you want to take with you on a mission. :)

More on the saga - I went ahead and set my next month's pay to Generous to go to Morale 32, and lo and behold, my next mission I was getting the 25 Resolve per combat turn I was supposed to be getting. I'll keep an eye on it to see if it holds for multiple missions while I'm at Morale 32, or if the Resolve drops back to 15 by itself. If it does, I'll bump up to Morale 33 next month and see if it comes back again.