。
She suggested we leave a little earlier.
Literal
She [topic-は] us [subject-が] more early depart-if how-about [quotative-と] said.
~たらどうか ('how about doing X / why don't you X') is a soft suggestion form. Built from the conditional ~たら + どう ('how') + か, it asks 'how would it be if X happened?' — a polite way to make a recommendation without commanding. The embedded subject is 私たち, marked by が. もっと早く ('more early / earlier') uses もっと to compare without an explicit standard ('more X than now / than expected'). The whole quoted clause is wrapped by と and reported via 言った.