(Updated April 23, 2024 for V0.007)

Pixel 7x15 has complete support for the following Unicode blocks:

Basic Latin
Latin-1 Supplement
Latin Extended-A
Latin Extended-B
IPA Extensions
Spacing Modifier Letters
Combining Diacritical Marks
Greek and Coptic
Cyrillic
Cyrillic Supplement
Armenian
Hebrew
Arabic
Arabic Supplement
Devanagari*
Thai
Georgian
Cherokee
Unified Canadian Aboriginal Syllabics
Runic
Unified Canadian Aboriginal Syllabics Extended
Combining Diacritical Marks Extended
Cyrillic Extended-C
Georgian Extended
Vedic Extensions
Phonetic Extensions
Phonetic Extensions Extended
Latin Extended Additional
General Punctuation
Superscripts and Subscripts
Currency Symbols
Letterlike Symbols
Number Forms
Arrows
Mathematical Operators
Enclosed Alphanumerics
Box Drawing
Block Elements
Geometric Shapes
Miscellaneous Symbols
Dingbats
Supplemental Arrows-A
Braille Patterns
Miscellaneous Symbols and Arrows
Latin Extended-C
Tifinagh
Cyrillic Extended-A
Ideographic Description Characters
CJK Symbols and Punctuation
Hiragana
Katakana
Bopomofo
Hangul Compatibility Jamo
CJK Strokes
Kana Phonetic Extensions
Enclosed CJK Letters and Months
CJK Compatibility
Latin Extended-D
Common Indic Number Forms
Devanagari Extended*
Latin Extended-E
Hangul Syllables
Alphabetic Presentation Forms
Arabic Presentation Forms-B
Halfwidth and Fullwidth Forms

and additionally:

Combining Diacritical Marks for Symbols: ◌⃰
CJK Unified Glyphs: U+4E00-U+53DD** and about 700 more characters based on simplicity. (Will work on an exact list.)
Arabic Presentation Forms-A: U+FB50-U+FBFF

* Also includes support for Devanagari conjuncts. Does not yet include support for Marathi or Nepali (but that shouldn't be too much work.)

** CJK support is in its initial phases, with a limited number of characters, and no Japanese, Korean or Vietnamese variants. This will continue to grow slowly over time.