Just-right

adj.calm, joyfuleveryday

What it means

Exactly suitable in size, degree, timing, or character.

Reach for it when praising a fit that is neither excessive nor insufficient

The smaller hall felt just-right for the acoustic quartet.

playful
Goldilocks
the audience will recognize a not-too-much, not-too-little comparison
not when Goldilocks is a cultural allusion and may trivialize consequential decisions.
warm
fitting
the choice suits the occasion and carries emotional appropriateness
not when Fitting can mean morally or ceremonially proper rather than precisely calibrated.
warm
perfect
enthusiastic praise for complete suitability is warranted
not when Perfect is absolute and often inflates a choice that merely works very well.
professional
suitable
requirements are met without emotional emphasis
not when Suitable sounds procedural and loses the sense of precise balance.
formal
ideal
the option satisfies all important requirements
not when Ideal can claim perfection beyond the measured fit implied by just-right.
formal
well-judged
a deliberate choice lands at the correct degree
not when Well-judged praises the decision-maker rather than the fit itself.
literary
apt
a word, example, or response fits neatly
not when Apt is uncommon in speech and does not suit every physical fit.

just-right balance
The recipe found a just-right balance between sweetness and acidity.
just-right size
The just-right size let children hold the tool safely.
just-right moment
She chose the just-right moment to invite questions.

Collins records the open phrase just right; the corpus uses an attributive hyphenated form.

The definition and the example on this page are written here. The dictionaries above ground which meaning is being described, not the wording.