Family & I went to the Poly in October (pre-Halloween, media week, Wishes, FTMagic time, etc.) when it was surprisingly busy.
We stayed on the Eastern side of the resort, in the Tahiti longhouse (yes, it was fantastic!) and found the TTC very, very convenient for our transportation needs . . .
We took the ~30 passenger launch back from MK one early PM and asked the 'captain' for his advice on exiting the park later that evening -- it was going to be a very busy night.
He suggested the Ferry since they were running 3 and each holds close to 600 people (twice the capacity of a monorail).
We always think monorail, since it's Disney's signature transportation mode, but the ferry was incredibly convenient too.
Lots of room to wheel on the sleeping toddler in his stroller. Big, wide ramps for lots of people to em/disembark.
With 3 ferries (I seem to recall 2 during the early AM's and mid-afternoon), the wait isn't much longer than that of the monorail. Even though the ferry goes a bit slower, it's a direct route across 7 Seas Lagoon (vs. the circumference).
Best of all, everyone gets on . . . with their child's stroller!