While there may be improvements overall duly noted in other posts since 6.5, here's an instance still hard to justify: (at least in my mind)
My team, the Stones, at bat top of the 7th ahead by two runs and one out, no one on. The first out came retiring my ninth hitter (DH league). The left-handed starter is relieved by another lefty to face my right-handed lead-off man. Now in and of itself, all right. Maybe the manager isn't set to favor matchups. The part that baffles me a bit is why this choice when it's a reliever who, the day before this one threw 44 pitches and has and Endurance of 25/100. One of the other relievers available, not the closer, was a 4-1/2 star (gold) right hander who hadn't thrown a pitch in five days. Maybe it's not way outta whack, but it's one of those marginal enough situations that seems to err on the side of "what's with the bullpen AI?"
Just my thoughts. Not assuming for a minute there's a reasonable panacea for this enduring, somewhat puzzling, aspect of the game. Only commenting on an observation during this testing process.
Edit: To his credit, both the reliever's and the manager's, two up two down groundballers and ended the top of the 7th. Results are everything I guess.
Edit#2: Maybe it's all a big nevermind. I don't know. The AI did bring in the better reliever in the 8th. Bottom of the 8th my setup man gives up 2 HRs allowing the game to tie. Both teams go to closers and his gives up a 3 run homer, mine gives up a solo and..... well, what did it all matter anyway, eh? Still.....got my eye on the pen.

Always room for improvement there.
Apologies for the little derail there, I'll try to refrain unless I spot something more obvious or have verified something else works. Sigh. The game gets ya worked up sometimes, you know?
Edit #3: Sorry. Just had to say, see what I know?! Nothing. The 4-1/2 star I'd wondered about actually got the loss facing 6 batters and allowing 1 of the 2 inherited to score. Thought this was an interesting box score note to top off my momentary assessment folly:
Ike Mann reaches a career high 5 consecutive losses.
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