Learn Hardcore Finnish: Onko sinulle tärkeämpää tarkka aikataulu vai kiireetön ilta kotona? - Is a precise schedule more important to you, or a relaxed evening at home?

The ending -ko / -kö is an enclitic that turns a statement into a yes–no question. It attaches to the first important word of the sentence. Often that is the verb:

Onko hän kotona? – Is he/she at home?
Oletko väsynyt? – Are you tired?

But it can also attach to some other element if you want to emphasize it:

Sinulleko se on tärkeää? – Is it important to *you (of all people)?*

In your sentence, Onko starts a yes–no/which-of-two question: Is X or Y more important to you?

Why is it sinulle and not sinua or sinun?

Sinulle is the allative case of sinä (you singular). The allative -lle often means to / for someone.

With adjectives like tärkeä (important), Finnish normally uses allative to express important to someone:

Tämä työ on minulle tärkeää. – This job is important to me.
Terveys on hänelle tärkeää. – Health is important to him/her.

So:

sinulle = to you / for you
sinua = partitive of you (used e.g. after some verbs: rakastan sinua – I love you)
sinun = genitive of you (your), showing possession: sinun kirjasi – your book

In Onko sinulle tärkeämpää…, the pattern is:

olla + tärkeä / tärkeää + (allative person)
to be important to someone

So sinulle is exactly the form required here: more important to you.

Why is it tärkeämpää and not tärkeämpi?

Both forms come from tärkeä (important), but they play different roles:

tärkeämpi = comparative nominative (more important as an adjective describing a specific thing)
tärkeämpää = comparative partitive (more important as a more abstract quality / evaluation)

In this sentence, tärkeämpää is in the partitive. Finnish often uses the partitive for predicative adjectives when you are talking about a general or abstract quality, especially with olla + tärkeä:

On minulle tärkeää, että tulet.
It is important to me that you come. (abstract importance)

Compare:

Tämä kirja on minulle tärkeä.
This book is important to me. (a concrete book described as important)

For the exact structure you have, the “template” is very common and natural:

Onko sinulle tärkeää/tärkeämpää X vai Y?

You could say:

Kumpi on sinulle tärkeämpi, tarkka aikataulu vai kiireetön ilta kotona?

Here tärkeämpi (nominative) fits, because now there is an explicit, concrete subject (kumpi = which one).

In short:

tärkeämpää here = typical partitive form in the pattern on (minulle) tärkeää/tärkeämpää + X, talking about “what (in general) is (more) important to you.”
tärkeämpi is more like “the one that is more important,” especially with kumpi.

Are tarkka aikataulu and kiireetön ilta kotona subjects or objects, and why are they in the nominative?

They are the things whose importance is being compared, essentially the “candidates” for what is more important.

Structurally, you can think of the sentence as:

(Se) onko sinulle tärkeämpää: tarkka aikataulu vai kiireetön ilta kotona?

There is no object here (the verb olla “to be” usually doesn’t take an object). The noun phrases are in nominative singular:

tarkka aikataulu – a precise schedule
kiireetön ilta kotona – an unhurried evening at home

In questions of the type:

Onko sinulle tärkeää X vai Y?

the X and Y alternatives are normally in the nominative, because they are the things we are evaluating, not objects in an action like “to see” or “to buy.”

How is the word tarkka used here, and does it change form?

Tarkka is an adjective meaning precise, exact, detailed. It’s in the basic form (nominative singular) here, modifying aikataulu (schedule).

tarkka aikataulu – a precise schedule, a strict timetable

Because aikataulu is singular nominative and not in any other case, the adjective agrees:

nominative singular noun → nominative singular adjective: tarkka aikataulu

If you changed the case, tarkka would change as well:

tarkan aikataulun (genitive): of a precise schedule
tarkkaa aikataulua (partitive): a precise schedule (as an object or partial thing)

But in your sentence we just have the basic tarkka aikataulu.

What does kiireetön literally mean, and how is it formed?

Kiireetön means unhurried, without rush, leisurely.

It is built from:

kiire – hurry, rush
suffix -ton / -tön – “without, lacking”

So kiireetön literally means without hurry.

This -ton / -tön suffix is common:

maidoton – dairy-free (without milk)
rasvaton – fat-free (without fat)
koditon – homeless (without a home)

In the sentence, kiireetön is in nominative singular, modifying ilta (evening):

kiireetön ilta – an unhurried / relaxed evening

Why is it kotona and not kotiin?

Both come from koti (home), but they are different local cases:

kotona – inessive: at home (location, where something is)
kotiin – illative: to home (direction, movement toward home)

In kiireetön ilta kotona, we are talking about an evening spent at home, without movement:

ilta kotona – an evening at home

If you talked about going home, you’d use kotiin:

Menemme kotiin. – We are going home.
Tulen illalla kotiin. – I’ll come home in the evening.

Can we change the word order, like Onko tarkka aikataulu vai kiireetön ilta kotona sinulle tärkeämpää? Does it sound different?

Yes, Finnish word order is quite flexible, and that sentence is grammatically fine:

Onko tarkka aikataulu vai kiireetön ilta kotona sinulle tärkeämpää?

Both versions are natural:

Onko sinulle tärkeämpää tarkka aikataulu vai kiireetön ilta kotona?
Onko tarkka aikataulu vai kiireetön ilta kotona sinulle tärkeämpää?

The main difference is focus / emphasis:

Version 1 starts with sinulle tärkeämpää, so it foregrounds the importance to you as a general concept.
Version 2 starts directly with the alternatives, a bit closer to English Is a precise schedule or an unhurried evening at home more important to you?

In everyday speech, both are possible. The original is slightly more “formulaic” for this kind of question about personal values.

Why is it vai and not tai?

Finnish has two main words for or:

vai – used in direct questions when presenting alternatives
tai – used in statements, and in questions where both options could be true or the distinction is not sharp

In questions like “X or Y?” where you’re choosing between alternatives, vai is the normal choice:

Haluatko teetä vai kahvia? – Do you want tea or coffee?
Onko se iso vai pieni? – Is it big or small?

So:

Onko sinulle tärkeämpää tarkka aikataulu vai kiireetön ilta kotona?
→ Which of these is more important to you?

Using tai here would sound odd or at least not idiomatic; a native would almost always say vai.

How would you answer this question naturally in Finnish?

A short, natural answer can just repeat the chosen option:

Tarkka aikataulu.
Kiireetön ilta kotona.