All other things being equal, how many syllables would you choose for first and middle(s)?
In my family, we have 3-3-2, 3-1-2, 2-2-2, 2-1-2, and 1-2-2, and they all sound wonderful.
I’ve always thought two-syllable surnames are the most flexible.
Well, my favorite names tend to be long and multisyllabic, so I would most likely go with 4-3, 3-4, 4-4, or 3-3. (Maybe even some combos with a five syllable name!) But I would probably say that regardless of how many syllables the last name was. I don’t get it when people say long names are “too much”. I’d rather a name be too much than too little, but that’s just my style.
With a two syllable surname, though, I think most combinations would work just fine. Maybe avoid 2-2 and 1-1, but even those can work with some names. More than syllables, it really depends on how the names are accented.
Thanks for the link, ellie. She and I are very much on the same page!
Syllables are one of my few peevey naming quirks, going along with rhyming and alliteration (for me they are all coming from the same source). I was 2-2-1 and took my husband’s name, now I’m 2-2-2 and the sing-songiness bugs me 
Of course, the majority of my favorite names are 2 syllables, and the 3 syllable names I like are just avenues to a 2 syllable nickname! My guess is we’ll end up with 2-3-2 or 2-1-2.