It may be easier to only be nice, but it isn’t always the most helpful. If you have feedback about something another person did or said that can actually help them improve or enhance their work or life, be helpful and share it. But be nice about it.

If you don’t bring it up, they may never improve in that area. Especially if you complimented them on a job well done – when you really saw that it needed some improvement.

When you say “great talk” to a mediocre talk, you aren’t being helpful. And really, you’re not being all that nice then either.
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Actually, bringing it up in a respectful way is compassionate and useful.

In a loving relationship, we should be able to accept useful feedback. Because we know that it is coming from a place of compassion and love, for the benefit of the receiver.

First, ask if they’d like to hear some insights or feedback. –> “Can I share some feedback?” “I have something to share about [your talk]. Are you interesting in hearing it?”

Once, you are granted permission, say it. Clearly, concisely, nicely. But don’t half-say it, or hint.

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Actually, give such feedback often. Make it part of your culture of your marriage, of helping each other grow. Ironically, the less often you give such feedback, the more critical it feels when it is received.