Hal sits next to 4 phonetic neighbors — Cal, Val, and Al are the closest matches by sound. Most share Hal's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"home ruler (from Henry)"
"allies, friends"
"shining, bright, luminous"
"from Bryans land"
"peace (folk etymology)"
"mountain of strength, exalted"
"he is Yah (God)"
"guardian, watchman"
"none compares to God"
"he will enlighten"
"God will strengthen"
"modern invented name combining Zay and lyn"
"brilliant, luminous one"
"loyal servant, devotion"
"famous wolf"
"lover of churches"
"of Mars, warlike"
"God has remembered"
"may God give strength"
"shining, bright (via Hebrew Meir)"
Similar sound: These names share phonetic patterns with Hal — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Germanic origins, giving them the same cultural heritage as Hal.
Rhythm: Hal is a 1-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.