Thread by @Atmaprajnananda

In Classical Sanskrit, the styles of stotras are many.

There are -
pañcakam (comprising five ślokas),
ṣaṭkam (comprising six ślokas),
aṣṭakam (comprising eight ślokas),
śatakam (with a hundred ślokas),
sāhasrī (with a 1,000 ślokas).

Nirvāṇaṣaṭkam is a ṣaṭkam.

All these are generally simple.
Rarely some of them sometimes contain long compounds leaning towards artificiality, especially when the subject matter is Tantric.
Some of such examples are -
Kanakadhārā-Stotra,
Mahiṣāsuramardinī-Stotra,
Saundaryalaharī.

Seeds of philosophical thoughts are there in some of the stotras like -

आत्मा त्वं गिरिजा मतिः सहचराः प्राणाः शरीरं गृहं
पूजा ते विषयोपभोगरचना निद्रा समाधिस्थितिः ।
सञ्चारः पदयोः प्रदक्षिणविधिः स्तोत्राणि सर्वा गिरो
यद्यत्कर्म करोमि तत्तदखिलं शम्भो तवाराधनम्‌ ॥
-शिवमानसपूजा 4

Dakṣiṇāmūrti-Stotram of Śaṅkara (Sureśwara has commented on it in Mānasollasa) is regarded as one of the most famous devotional poems.

The later the stotra, less is its merit.

A highly popular Mahiṣāsuramardinī-Stotra, contain anomalies & blunders in grammar & metre.

Most of the stotras are composed in Anuṣṭup (as used in Rāmāyaṇa & Mahābhārata) or Triṣṭup (used in Bhagavadgītā), or Vasantatilakā(portions of Kanakadhārā-Stotram), Śārdulavikrīḍita (Dakṣiṇāmūrti-Stotram), and though rarely Ārya which's used by hymnologists gracefully.

We have hymns in vernacular languages also.
There are works of the Aḷwars (Tamil),
Vidyāpati (Maithili),
Tulasidās (Avadhi),
Suradās (Braja Bhasha),
Mirābai (Rajasthani and Braj Bhāshā),
Kabir ( Hindi, borrowing from various dialects including Avadhi, Braj, and Bhojpuri),

Nānak (Gurmukhi),
Jnāneswar (Marathi),
Tukāram (Marathi),
Narsimhadas Mehta (Gujarati),
Purandara Dāsa (Kannada),
Tyāgarājā (Telugu and Sanskrit),
Jagannātha Dāsa (Odia ),

are high class hymnologists.

(Excerpts from my forthcoming book
"Hymnology - Suktas and Stotras")