We have a dashboard page that consists of many web parts displaying data
from subsites (think one master site showing views from multiple
subsites). Performance is not great, as there is a hit for each web
part on binding to the grid (the webpart appears like a view of the
underlying list data).

Any suggestions on how to optimize this loading? Can we get the webpart
page (not a custom page, is a normal content page - or do we need to use
one) to load these async?