Dallas sits next to 4 phonetic neighbors — Dawson, Davis, and Dalton are the closest matches by sound. Most share Dallas's Scottish cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"meadow dwelling, water meadow"
"mountain of strength; exalted"
"little fire (via Aidan variant)"
"full of goodness"
"hollow (place)"
"shelter, dwelling"
"cart driver, transporter of goods"
"son of Elias"
"may God protect"
"little warrior, war-associated"
"Mack's spring, great stream"
"God is gracious"
"one who lives by the river"
"dispenser of provisions, household steward"
"stranger, foreigner"
"helpful; assistant; descendant of the helpful one"
"strength, dominance"
"the honored defender"
"free, liberated"
Similar sound: These names share phonetic patterns with Dallas — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Scottish Gaelic origins, giving them the same cultural heritage as Dallas.
Rhythm: Dallas is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.