The Ethiopian alphabet (abougida) has this feature, but it goes one step further. Every vowel consonant pair (aka every syllable) has it’s own symbol. That sounds like a lot of symbols, and it is, but the beauty of it is that the vowel sounds are just modifiers of the consonant. So you only have to memorize the consonant symbols and the modifiers and you can reduce drastically reduce the number of letters needed plus have a completely phonetic writing system.