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"
"coal town, dark settlement"
"beauty, grace, excellence"
"park keeper"
"he who descends, descent"
"descendant of Rían (little king)"
"Poecc's estate; Poecc's settlement"
"Scottish form of John, gift of God"
"holy person; one recognized for virtue and closeness to God"
"descendant of the ruler of the home"
"descendant of Grádaigh"
"supplanter's son (via James → Jacob)"
"shelter, dwelling"
"hollow (place)"
"from Attica, man of Athens"
"dweller near the woods"
"little red-haired one"
"good fortune, luck"
"descendant of the dark one"
"southern settlement, south farm"
"friendly, allies, friend"
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.