I'm studying MSA and the Syrian dialect. Here's my perspective.
The morphology is simpler in dialects:
- No cases
- No diacritics on verb endings (in particular you don't have to distinguish between subjunctive and jussive anymore).
- Verb conjugation is simpler (in particular verbs have no dual form)
That's about it. There is still a triconsonantal root system, genders, and irregular plurals. However there are tons of things outside morphology that are more difficult.
1) Phonology is more difficult -- because of how short vowels get dropped or auxiliary vowels get inserted depending on the length of consonant clusters
2) Syntax is more difficult. There are more tenses, there is a new subjunctive, and the word order is much more free than MSA's VSO.
3) Idioms: Dialects are richer in them. MSA is formal and its idioms are mostly transparent, and dialects can really make you scratch your head!
4) There is a lack of learning materials for dialects.
There is this nice PDF that describes differences between MSA and the Levantine dialects:
http://teammaha.com/wp-content/uploads/ ... -Shami.pdfteammaha.com is an amazing website to learn more about dialects (mainly Levantine and Egyptian).
Here is an interesting excerpt from the PDF above regarding the verbs in dialects:
Verbs in Shami are almost as complex as they are in fuSHa. Like other dialects the fuSHa manSuub
and majzuum and their unique triggers are gone, but in their place Shami has developed a
distinction between a normal, declarative present tense (with a b- prefix) and a new subjunctive
(lacking the prefix). The fuSHa future (sawf, sa-) is replaced by a variety of particles and prefixes (ra7,
la7, la-, 7a-). Shami also has a continuous form, completely lacking in fuSHa. Like other dialects, it
also makes much broader use of participles than MSA does.