The dyslexia point is interesting; yes, English orthography causes more reading disorders than languages with more regular spelling-to-sound mappings (Italian, Finnish, etc.). That's consistent with the parser having to work harder when the signal is noisier.

Your intuition about "slower more intentional parsing" connects to something I'm exploring: we may parse language at two levels simultaneously; a fast, nearly autonomic level (think: how insults land before you consciously process them) and a slower deliberate level. Whether those levels interact differently across languages is an open question.

First: dyslexia has little to do with parsing, which is generally understood to relate to structure/relations between words.

Second: multiple levels of language processing have been identified, although it's not at all clear how well separated they are. The higher levels (semantics, pragmatics) are by necessity lagging behind the lower (phonetics, syntax). The higher levels also seem more "deliberate."